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Suppressive effects of lamotrigine on the development and expression of tolerance to morphine-induced antinociception in the male mouse
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a v a i l a b l e a t w w w. s c i e n c e d i r e c t . c o m
w w w. e l s e v i e r. c o m / l o c a t e / b r a i n r e s
Research Report
Suppressive effects of lamotrigine on the development and expression of tolerance to morphine-induced antinociception in the male mouse Mehdi Saberi a,c,⁎, Behzad Chavooshi b,c a
Department of Pharmacology and Toxicology, Applied Neuroscience Research Center, Faculty of Medicine, Baqiyatallah Medical Sciences University, P.O. Box 19568, Tehran, Iran b Department of Psychology, Faculty of Psychology and Education, University of Tehran, Tehran, Iran c Neuroscience Research Center, Shahid Beheshti University, M.C., Tehran, Iran
A R T I C LE I N FO
AB S T R A C T
Article history:
Previous studies have demonstrated that some anticonvulsant drugs can modulate
Accepted 6 July 2009
tolerance to the opioid analgesia. In the present study, the effects of lamotrigine (LTG) on
Available online 15 July 2009
the development and expression of tolerance to the morphine-induced antinociception were evaluated using tail-flick test. To assess the LTG effects on tolerance development, the
Keywords:
animals received LTG (3, 10 or 30 mg/kg; i.p.), 30-min prior to morphine (50 mg/kg; s.c.)
Lamotrigine
administration during tolerance induction period once daily for 3 days. Also, to evaluate the
Morphine
effects of LTG on tolerance expression, different doses of LTG were administered 30-min
Tolerance
before challenge dose of morphine (4 mg/kg; s.c.) following morphine-induced tolerance. In
Antinociception
each experiment the antinociceptive response to the challenge dose of morphine was
Tail-flick test
evaluated before (on day 1) and after tolerance induction (on day 4) every 30-min till 2 h by
Mouse
tail-flick test. Furthermore, the analgesic effect of various doses of LTG alone or with the challenge dose of morphine was evaluated as well. The results showed that LTG at the doses of 10 and 30 mg/kg could inhibit the development of tolerance. Also, LTG at the dose of 30 mg/kg attenuated the expression of morphine-induced tolerance. LTG alone injection was associated significantly with higher latency period when compared to the control group. Moreover, LTG (10 and 30 mg/kg) significantly enhanced antinociceptive effect of morphine challenge dose in non-tolerant animals. These data indicated that, while LTG can attenuate both development and expression of morphine-induced tolerance, it can enhance morphine-induced antinociception. These effects may have important clinical implications. © 2009 Elsevier B.V. All rights reserved.
1.
Introduction
Opioid drugs are currently the most potent and effective analgesics which are used to relieve moderate to severe pains. However, long-term administration of opioids can alter the
central pain-related systems and lead to the development of tolerance (Ballesteros-Yanez et al., 2008; Hernández et al., 2009). On the other hand, non-opioid drugs are proposed to enhance opioid analgesia and may attenuate their side effects (Way et al., 2001; Lin et al., 2008). Several anticonvulsant drugs
⁎ Corresponding author. Department of Pharmacology and Toxicology, Faculty of Medicine, Baqiyatallah Medical Sciences University, P.O. Box 19568, Tehran, Iran. Fax: +98 21 22830262. E-mail address: [email protected] (M. Saberi). 0006-8993/$ – see front matter © 2009 Elsevier B.V. All rights reserved. doi:10.1016/j.brainres.2009.07.014
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have been shown to treat neuropathic pain conditions because of their effects on voltage- and ligand-gated channels in central pain pathways (Todorovic et al., 2003; Lin et al., 2005). Recent studies suggest that anticonvulsants might decrease opioid consumption either by enhancing opioid analgesia or by suppressing mechanisms of opioid tolerance (Gilron, 2006). For example, carbamazepine (Sahebgharani et al., 2006), phenytoin (Webb and Kamali, 1998), gabapentine (Wiffen et al., 2005), topiramate (Lopes et al., 2009) and vigabatrin (Alvez et al., 1999) have been shown to increase opioids antinociception. Other studies have also revealed that anticonvulsant drugs suppress opioid tolerance (Tamayo and Contreras, 1983; Kosten et al., 1995; Zullino et al., 2002; Zullino et al., 2004; Gilron et al., 2005; Chavooshi et al., 2009). The results of these studies raise the question as to whether such suppressive effect of anticonvulsants is merely a general characteristic of all anticonvulsant drugs or is a specific effect to a certain class of anticonvulsants which may be effective in attenuating morphine-induced tolerance. It has been reported that lamotrigine (LTG) is effective against trigeminal neuralgia refractory to the other treatments, HIV neuropathy, and central post-stroke pains (Backonja, 2002; Silver et al., 2007). In addition, LTG has been shown to induce analgesia in neuropathic pains such as intractable sciatica (Eisenberg et al., 2003) and other models of chronic pains (Hunter et al., 1997; Klamt, 1998; Jensen, 2002; Lee et al., 2002) as well as dynorphin-induced chronic allodynia (Laughlin et al., 2002). However, the antinociceptive effect of LTG in acute pain and in animal models of pain such as tail-flick test has not been fully studied (Laughlin et al., 2002). LTG acts on voltage-dependent Na+ channels to decrease the pre-synaptic release of the excitatory amino acid neurotransmitter-glutamate (Shuaib et al., 1995; Lin et al., 2005; Tsenov et al., 2009) and also can increase the release of GABA, an inhibitory neurotransmitter (Cunningham and Jones, 2000). On the other hand, it has been shown that increment of glutamate or decrements of GABA are involved in morphineinduced tolerance (Asl et al., 2008; Lin et al., 2008). So, it could be suggested that LTG may influence the tolerance to the morphine's analgesia. Additionally, although it has been shown that LTG may represent a useful agent for the treatment of opiate abstinence (Lizasoain et al., 1996), there is no evidence regarding the influence of LTG on the development and expression of morphine-induced tolerance. Therefore, the present study attempted to bring additional evidence to show the effect of LTG on morphine's analgesia and its effects on the development and expression of tolerance to morphine-induced antinociception in the setting of acute nociception through tail-flick assay in mice.
2.
Results
2.1. Experiment (1): Development of tolerance to morphine-induced antinociception The antinociceptive response to a challenge dose of morphine (4 mg/kg; s.c.) for saline and pre-tolerant groups on day 1 was almost similar without any difference at all time set of intervals (Fig. 1A). To assess the morphine tolerance in this
Fig. 1 – The effect of challenge dose (4 mg/kg; s.c.) of morphine, (A) before tolerance induction on day 1 and, (B) following 3 consecutive days administration of saline 10 ml/kg ( ) or morphine 50 mg/kg ( ) as an induction period on day 4. Each point represents the mean ± SEM of percent of maximal possible effect (%MPE) for 7–8 mice. **P < 0.01, ***P < 0.001 compared to saline-treated group.
○
●
study, animals received morphine (50 mg/kg) or saline (10 ml/ kg) once daily for 3 days. Fig. 1B shows the development of tolerance to morphine-induced antinociception tested by challenge dose of morphine (4 mg/kg; s.c.). Two-way ANOVA indicated that the antinociceptive response (the mean of %MPE values) to the challenge dose of morphine on day 4 decreased significantly in morphine-treated animals that received morphine during the induction period in comparison with the saline-treated group [F(1,48) = 69.12, P < 0.0001; Fig. 1B] at all time set intervals. These findings are clearly indicative of the development of tolerance to morphine-induced antinociception following 3 days of morphine treatment. Moreover, the baseline TF latencies were 2 ± 0.24 s and 2.9 ± 0.16 s for saline and tolerant groups on day 4 respectively, and had significant differences when compared by unpaired t-test (P < 0.05).
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2.2. Experiment (2): Effects of LTG on the development of morphine-induced tolerance In this set of experiment, the animals were injected with different doses of LTG (3, 10 or 30 mg/kg; i.p.), 30 min before morphine (50 mg/kg; s.c.) administration once daily for 3 days during the induction period. Our data obtained in Fig. 2 revealed that pretreatment of animals with LTG significantly reduced the development of tolerance to morphine antinociceptive effect in a dose-dependent manner, as indicated by increment of %MPE in LTG treatment groups. However, the lowest dose of LTG (3 mg/kg) had no effect on the development of morphine tolerance. Two-way ANOVA followed by Tukey's post test indicated that in morphine-treated animals that received various doses of LTG prior to morphine during the induction period, the antinociceptive responses to the challenge dose of morphine (4 mg/kg; s.c.) on day 4 significantly increased in comparison to vehicle group that received Tween-80 instead of LTG [F(3,96) = 36.56, P < 0.0001; Fig. 2]. Also, the averages of baseline TF latencies on day 4 were; 2 ± 0.16, 3.3 ± 0.12, 3.1 ± 0.11 and 3.2 ± 0.31 for vehicle, 3, 10 and 30 mg/kg of LTG treatment groups respectively and showed statistically significant difference (P < 0.05). Moreover, in animal which received the highest dose of LTG (30 mg/kg) alone for 3 days there was no additive effect on the antinociceptive response to the challenge dose of morphine on day 4 in comparison to those in control group [F(1,48) = 3.4, P = 0.0617; Fig. 3]. The averages of baseline TF latencies on day 4 were 2 ± 0.33 and 3 ± 0.32 for vehicle and LTG 30 mg/kg, respectively.
2.3. Experiment (3): The effect of LTG on the expression of morphine-induced tolerance
Fig. 3 – The antinociceptive response of single challenge dose of morphine (4 mg/kg) after 3 days co-administration of lamotrigine (LTG) at the dose of 30 mg/kg with saline (solvent of morphine, 10 ml/kg) ( ) or saline alone ( ) on percent of maximal possible effect (%MPE) values at 30-min set intervals on the fourth day. Each point represents the mean ± SEM for 7–8 mice.
●
○
dose prior to challenge dose of morphine (tolerance expression) was sufficient. Thus, the animals received LTG (3, 10 or 30 mg/ kg; i.p.) or vehicle, 30 min before challenge dose of morphine (4 mg/kg) prior to and following morphine-induced tolerance. Two-way ANOVA followed by Tukey's post test indicated that
We next examined whether LTG blockade of morphine tolerance, required daily administration of LTG or if a single
Fig. 2 – The effect of different doses of lamotrigine (LTG) on development of morphine tolerance. Animals received LTG (3, 10 or 30 mg/kg; i.p.) or vehicle (Tween-80, 1%; 10 ml/kg; i.p.), 30 min before morphine (50 mg/kg; s.c.) once daily for 3 days during the induction period. On day 4, the tail-flick latencies were determined after injection of challenge dose of morphine (4 mg/kg; s.c.). Each point represents the mean ± SEM for 7–8 mice. *P < 0.05, ***P < 0.001 compared to saline group.
Fig. 4 – The effect of different doses of lamotrigine (LTG) on the expression of morphine-induced tolerance following 3 days of morphine tolerance induction (50 mg/kg; once daily). Various doses of LTG or vehicle (Tween-80, 1%) were administered 30 min prior to injection of challenge dose of morphine (4 mg/kg; s.c.) on day 4. Each point is the mean ± SEM of percent of maximal possible effect (%MPE) for 7–8 mice. †, * indicate significance in comparison to the morphine-treated (tolerant) and vehicle-treated (non-tolerant) groups, respectively, †††P < 0.05, or ***P < 0.001.
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administration of LTG (30 mg/kg) attenuated the expression of morphine tolerance [F(3,96) = 73.41, P < 0.0001; Fig. 4] at all time set intervals. The averages of baseline TF latencies on day 4 were; 2 ± 0.19, 2.1 ± 0.22, 3.1 ± 0.15 and 2.7 ± 0.34 for vehicle, 3, 10 and 30 mg/kg of LTG treatment groups respectively and showed statistically significant difference (P < 0.05).
2.4. Experiment (4): The antinociceptive effects of LTG and its combination with morphine To determine the effect of LTG on antinociceptive response of morphine, tail-flick tests were done for each animal at 0.5, 1, 1.5 and 2 h after single injection of LTG (3, 10 or 30 mg/kg; i.p.). Data analysis indicated that LTG (30 mg/kg) could significantly increase the %MPE when compared to those of control group [F (3,96) = 9.38, P < 0.0001; Figs. 5A, B]. In addition, to evaluate the effects of LTG on morphineinduced antinociception, the animals received various doses of LTG (3, 10 or 30 mg/kg; i.p.), 30 min before morphine (4 mg/ kg; s.c.) injection. Two-way ANOVA indicated that the coadministration of LTG (30 mg/kg) with morphine (4 mg/kg) significantly increased the %MPE in comparison to morphine alone treated group [F(3,96) = 10.58, P < 0.0001; Figs. 6A, B].
Fig. 6 – Effects of the different doses of lamotrigine (LTG) or vehicle (Tween-80, 1%) in combination with morphine (Mor) in (A) the average of tail-flick latencies and, (B) the percent of maximal possible effect (%MPE). The animals received LTG (3, 10 or 30 mg/kg), 30 min before morphine administration. Each point is the mean ± SEM for 7–8 mice. **P < 0.01; ***P < 0.001 compared to morphine-treated group.
3.
Fig. 5 – The antinociceptive effects of the different doses of lamotrigine (LTG) alone or vehicle (Tween-80, 1%) in (A) the average of tail-flick latencies and, (B) the percent of maximal possible effect (%MPE). Each point is the mean ± SEM for 7–8 mice. ***P < 0.001 compared to vehicle-treated group.
Discussion
The major findings of the present study were: (1) LTG attenuated the development of morphine-induced tolerance, (2) LTG attenuated the expression of tolerance to the antinociceptive effect of morphine, (3) LTG enhanced the antinociceptive effect of morphine in a dose-dependent manner and (4) LTG exhibited antinociceptive effect in the tail-flick test as an acute pain model. Although, the base line latencies for the saline groups were lower than other treated groups before challenge dose of morphine administration (because of the effects of treatments till day 4), the data were normalized using %MPEs. One of the major problems associated with the chronic use of morphine is tolerance. Repeated uses of morphine to relieve pain often cause patients to develop increasing resistance to
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the effects of the drugs, so that progressively higher doses are require to achieve the same analgesic effects (Yamamoto et al., 2000; Stoller et al., 2007; Zhang and Sweitzer, 2008). In the present study, we showed that LTG pretreatment can inhibit the development of morphine tolerance in a dosedependent manner. Our results are in agreement with the data from previous studies suggesting that anticonvulsant drugs attenuate opioid tolerance (Tamayo and Contreras, 1983; Kosten et al., 1995; Zullino et al., 2002; Zullino et al., 2004; Chavooshi et al., 2009). Given that different analgesic mechanism(s) for LTG and morphine and those underlying opioid tolerance are still unclear, understanding the interaction between these two drugs becomes difficult. One common link between morphine-induced tolerance and LTG analgesia is the modulation of glutamate receptors (Nishikawa et al., 2004; Lin et al., 2005; Lin et al., 2008). Also, previous studies showed that GABAergic system could play a role in the progression of morphine tolerance (Morgan et al., 2003; Asl et al., 2008). On the other hand, it showed that LTG increases GABA release (Cunningham and Jones, 2000). Hence, it could be concluded that increase of GABA release by LTG plays an inhibitory role for the development of morphine tolerance. Moreover, recent evidence suggests that nitric acid (NO), an endogenous molecule implicated in the regulation of a number of physiologic and pathogenic processes, is involved in the development of morphine tolerance (Ozek et al., 2003; Heinzen and Pollack, 2004). It seems that NO production via activation of N-methyl-D-aspartate (NMDA) receptors results in morphine tolerance (Pasternak, 2007). There are many reports showing that blockade of nitric oxide synthase (NOS) results in attenuation of morphine tolerance as well (Kolesnikov et al., 1993; Majeed et al., 1994; Dambisya and Lee, 1996; Homayoun et al., 2002). Lizasoain et al. (1996) showed that nitric oxide is involved in the suppression of morphine withdrawal symptoms during LTG treatment. Thus, it could be suggested that NO might be involved in attenuation of morphine tolerance by LTG. However, further studies are needed to confirm these aforementioned hypotheses. It has been previously reported that the development and expression of morphine-induced tolerance are distinct phases (Taylor and Fleming, 2001). Our results indicate that LTG can attenuate the expression of morphine's tolerance. Based on the analgesic effect of LTG alone and also its additive analgesic effect on morphine's challenge dose, it seems that the expression is more attenuated by additive effect of LTG than reversal of tolerance. In terms of its clinical effects, LTG especially is effective against trigeminal neuralgia, painful peripheral neuropathy, and post-stroke pain (Jensen, 2002). Animal experiments have shown the analgesic effects of LTG in painful conditions, such as dynorphin-induced chronic allodynia and formalin (Laughlin et al., 2002, Shannon et al., 2005) and cold-pressor tests (Webb and Kamali, 1998) as well as chronic constriction injury and hyperalgesia models in rats (Hunter et al., 1997; Klamt, 1998; Klamt and Posner, 1999). The results of this study showed that LTG had an important antinociceptive effect in acute condition. In contrast, Laughlin et al. (2002) have shown that LTG is ineffective in hotplate test. However hotplate test consists of stimulating the four limbs and even the tail of the animal simultaneously (Le Bars
et al., 2001). Such heterotopic stimuli involving large body areas undoubtedly trigger diffuse inhibitory controls that are likely to disturb the observed responses (Tjolsen and Hole, 1997). Several studies have indicated the involvement of the voltage activated sodium channels in LTG-induced antinociception via preventing the release of excitatory neurotransmitters (Leach et al., 1986; Teoh et al., 1995). Also, LTG inhibits sustained repetitive neuronal firing (Cheung et al., 1992) through increase of GABA release (Kuzniecky et al., 2002; Finnerup et al., 2002). These properties of LTG are suggestive of a drug having antinociceptive action. In the other set of our experiments, the effect of LTG on antinociceptive response of morphine was evaluated. We show that LTG enhances morphine's antinociceptive effects in tail-flick test. Our results are in agreement with the data from previous studies suggesting that the combination of morphine and LTG produced a dose-related antinociceptive effect, in rats in a formalin test (Arguelles et al., 2002). As a result, coadministration of drugs such as LTG with morphine which can produce therapeutic analgesia with lower dose of morphine would be of great clinical implication. In conclusion, based on the aforementioned findings and the observed analgesic effects of LTG alone as well as its ability to attenuate the development and expression of morphine tolerance, co-administration of LTG and morphine may be worthwhile for clinical applications.
4.
Experimental procedures
4.1.
Animals
One hundred and twenty adult male albino NMRI mice (Pasteur Institute, Iran) weighing 20–25 g were used in these experiments. They were kept 8–10 per cage (45 × 30 × 15 cm) at a room controlled temperature (23 ± 1 °C) and maintained on a 12-h light/dark cycle (light on 07:00 h) with free access to the standard rodent breeding diet and tap water. Each animal was used only once and killed immediately after the experiment. All experiments were performed in accordance with the Guide for the Care and Use of Laboratory Animals (National Institutes of Health Publication No. 80–23, revised 1996) and were approved by the Research and Ethics Committee of Tehran University. 4.2.
Drugs preparation
Morphine sulphate (Temad Co, Iran) dissolved in saline and lamotrigine (Baakhtar Co, Iran) were suspended in 1% solution of Tween-80 (Sigma, USA) in saline. The LTG and morphine were prepared immediately before use and injected intraperitoneally (i.p.) and subcutaneously (s.c.) in a volume of 10 ml/kg, respectively. 4.3.
Assessment of morphine antinociception
Nociception was assessed with the tail-flick apparatus (D'amour and Smith, 1941). Before the test, animals were allowed to adapt to the conditions of the laboratory room for at least 1 h. Moreover, animals were alternatively
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allocated in their restrainers for 1 min each 15 min before the test in order to attenuate the stress that has been shown to produce antinociception. Restrained animals were placed on the tail-flick apparatus (type 812, Hugo Sachs Elektronik, Germany), a noxious beam of light was focused on the tail about 4 cm from the tip, and tail-flick latency was recorded automatically. Tail-flick latency (TFL) is a spinal response and, therefore, TFL is a measurement of pain threshold at the spinal level. The intensity of the radiant heat source was adjusted to yield baseline latencies between 1.8 and 4 s, this intensity was never changed and any animal whose baseline latency was outside the pre-established limits was excluded from the experiments. In order to minimize injury in the animals, a cut-off time of 8 s was used. Baseline latency was assessed in duplicate with 30-min intervals and recorded as an average of TFL time. TFL sec are expressed as percentage of maximal possible effect (%MPE) which was calculated from the following formula: kMPE=
4.4.
Post drug latency ðsecÞ Baseline latency ðsecÞ 100: Cut off value ðsecÞ Baseline latency ðsecÞ
Experimental protocols
4.4.1. Experiment (1): Development of tolerance to morphine-induced antinociception Tolerance induction was begun on day 1, 4 h after challenge dose of morphine (4 mg/kg; s.c.) by administration of morphine (50 mg/kg; s.c.) or saline (10 ml/kg; as control) once daily for 3 days as has been previously described (Zarrindast et al., 2002). The antinociceptive response to a challenge dose of morphine (4 mg/kg; s.c.) was determined by tail-flick test at 30-min intervals (0.5, 1, 1.5 and 2 h) on day 1 and day 4 for tolerance evaluation (n = 7–8 in each group). The challenge dose of morphine was selected as already described by Hienzen and Pollack (2004). 4.4.2. Experiment (2): Effects of LTG on the development of morphine-induced tolerance In these experiments, to evaluate the effects of LTG on the induction of morphine's tolerance, animals (n = 7–8) received various doses of LTG (3, 10 or 30 mg/kg; i.p.), 30 min before morphine (50 mg/kg; s.c.) or vehicle (Tween-80, 1%) once daily for 3 consecutive days. The effect of the challenge dose of morphine (4 mg/kg; s.c.) was tested on day 1 prior to and on day 4 following the induction period of morphine tolerance at different time set intervals as cited above. The doses of LTG were selected based on previous study that evaluated the antinociceptive action of LTG, which is lower than those used as anticonvulsants in experimental models in mice (Christensen et al., 2001). Also, the animals in separated groups (n = 7–8), were treated with high dose of LTG or saline alone for 3 days and then the response to challenge dose of morphine was only tested on the 4th day (test day) to determine whether there are carryover interactions between repeated LTG administration and subsequent morphine testing.
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4.4.3. Experiment (3): The effect of LTG on the expression of morphine-induced tolerance In this set of experiments, to assess the effects of LTG on the expression of morphine-induced tolerance, animals (n = 7–8) received different doses of LTG (3, 10 or 30 mg/kg) or vehicle (Tween-80, 1%), 30 min before challenge dose of morphine (4 mg/kg) following morphine-induced tolerance. The antinociceptive responses to the challenge dose of morphine for each animal were determined by tail-flick test on day 4 (post- tolerance induction) at different time set intervals, as described in section 4.4.1. 4.4.4. Experiment (4): The antinociceptive effects of LTG and its combination with morphine The antinociceptive effects of various single doses of LTG (3, 10 or 30 mg/kg) alone or vehicle (Tween-80, 1%) were determined at different time set intervals (0.5, 1, 1.5 and 2 h), 30 min post-injection. Also, the analgesic response of LTG in combination with morphine (4 mg/kg; s.c.) was evaluated as cited above. The animals (n = 7–8) received either LTG or vehicle (Tween-80, 1%), 30 min prior to morphine injection. 4.5.
Statistical analysis
The results obtained are expressed as mean ± SEM (standard error of mean). The mean MPEs in all groups were subjected to one-way and/or two-way ANOVA followed by Tukey's post test for multiple comparisons between groups, as needed. Data were processed by commercially available software GraphPad Prism® 5.0. P-values less than 0.05 were considered to be statistically significant.
Acknowledgments This work was supported by the Neuroscience Research Center, Shahid Beheshti University, M.C., Tehran, Iran. We thank Dr. Abolhassan Ahmadiani for his excellent technical assistance. REFERENCES
Alvez, D.A., Castro-Costa, C., Charvalho, A., Santos, F., Silveira, D., 1999. Possible analgesic effect of vigabatrin in animal experimental chronic neuropathic pain. Arq. Neuropsiquiatr. 57, 916–920. Arguelles, C.F., Torres-Lopez, J.E., Granados-Soto, V., 2002. Peripheral antinociceptive action of morphine and the synergistic interaction with lamotrigine. Anesthesiology 96, 921–925. Asl, B.H., Hassanzadeh, K., Khezri, E., Mohammadi, S., 2008. Evaluation the effects of dextromethorphan and midazolam on morphine induced tolerance and dependence in mice. Pak. J. Biol. Sci. 11, 1690–1695. Backonja, M.M., 2002. Use of anticonvulsants for treatment of neuropathic pain. Neurology 591, 4–17. Ballesteros-Yanez, I., Ambrosio, E., Pérez, J., Torres, I., Miguéns, M., García Lecumberri, C., DeFelipe, J., 2008. Morphine selfadministration effects on the structure of cortical pyramidal cells in addiction-resistant rats. Brain Res. 1230, 61–72. Chavooshi, B., Saberi, M., Tehrani, S.P., Bakhtiarian, A., Ahmadiani, A., Haghparast, A., 2009. Vigabatrin attenuates the
38
BR A IN RE S EA RCH 1 2 91 ( 20 0 9 ) 3 2 – 39
development and expression of tolerance to morphine-induced antinociception in mice. Pharmacol. Biochem. Behav. 93, 155–159. Cheung, H., Kamp, D., Harris, E., 1992. An in vitro investigation of the action of lamotrigine on neuronal voltage-activated sodium channels. Epilepsy Res. 13, 107–112. Christensen, D., Gautron, M., Guilbaud, G., Kayser, V., 2001. Effect of gabapentin and lamotrigine on mechanical allodynia-like behaviour in a rat model of trigeminal neuropathic pain. Pain 93, 147–153. Cunningham, M.O., Jones, R.S.G., 2000. The anticonvulsant, lamotrigine decreases spontaneous glutamate release but increases spontaneous GABA release in the rat entorhinal cortex in vitro. Neuropharmacology 39, 2139–2146. Dambisya, Y.M., Lee, T.L., 1996. Role of nitric oxide in the induction and expression of morphine tolerance and dependence in mice. Br. J. Pharmacol. 117, 914–918. D'amour, F.E., Smith, D.L., 1941. A method for determining loss of pain sensation. J. Pharmacol. Exp. Ther. 72, 74–79. Eisenberg, E., Damunni, G., Hoffer, E., Baum, Y., Krivoy, N., 2003. Lamotrigine for intractable sciatica: correlation between dose, plasma concentration and analgesia. Eur. J. Pain 7, 485–491. Finnerup, N.B., Gottrup, H., Jensen, T.S., 2002. Anticonvulsants in central pain. Expert. Opin. Pharmacother 3, 1411–1420. Gilron, I., 2006. The role of anticonvulsant drugs in postoperative pain management: a bench-to-bed-side perspective. Can. J. Anesth. 53, 562–571. Gilron, I., Bailey, J.M., Tu, D., Holden, R.R., Weaver, D.F., Houlden, R.L., 2005. Morphine, gabapentin or their combination for neuropathic pain. N. Engl. J. MED. 352, 1324–1334. Heinzen, E.L., Pollack, G.M., 2004. The development of morphine antinociceptive tolerance in nitric oxide synthase-deficient mice. Biochemi. Pharmacol. 67, 735–741. Hernández, L., Romero, A., Almela, P., García-Nogales, P., Laorden, M.L., Puig, M.M., 2009. Tolerance to the antinociceptive effects of peripherally administered opioids: expression of β-arrestins. Brain Res. 1248, 31–39. Homayoun, H., Khavandgar, S., Namiranian, K., Dehpour, A.R., 2002. The effect of cyclosporin A on morphine tolerance and dependence: involvement of larginine/nitric oxide pathway. Eur. J. Pharmacol. 452, 67–75. Hunter, J.C., Gogas, K.R., Hedley, L.R., Jacobson, L.O., Kassotakis, L., Thompson, J., Fontana, D.J., 1997. The effect of novel anti-epileptic drugs in rat experimental models of acute and chronic pain. Eur. J. Pharmacol. 324, 153–160. Jensen, T.S., 2002. Anticonvulsants in neuropathic pain: rationale and clinical evidence. Eur. J. Pain 6, 61–68. Klamt, J.G., 1998. Effects of intrathecally administered lamotrigine, a glutamate release inhibitor, on short- and long-term models of hyperalgesia in rats. Anesthesiology 88, 487–494. Klamt, J.G., Posner, J., 1999. Effects of lamotrigine on pain-induced chemo somatosensory evoked potentials. Anaesthesia 54, 774–777. Kolesnikov, Y.A., Pick, C.G., Ciszewska, G., Pasternak, G.W., 1993. Blockade of tolerance to morphine but not to kappa opioids by a nitric oxide synthase inhibitor. Proc. Natl. Acad. Sci. U. S. A. 90, 5162–5166. Kosten, T.A., DeCaprio, J.L., Rosen, M.I., 1995. The severity of naloxan-percipitate opiate withdrawal is attenuated by felbamate, a possible glycine antagonist Neuropsychopharmachology 13, 23–33. Kuzniecky, R., Ho, S., Pan, J., Martin, R., Gilliam, F., Faught, E., Hetherington, H., 2002. Modulation of cerebral GABA by topiramate, lamotrigine, and abapentin in healthy adults. Neurology 58, 368–372. Laughlin, T.M., Tram, K.V., Wilcox, G.L., Birnbaum, A.K., 2002. Comparison of acute, prolonged, and chronic nociception. J. Pharmacol. Exp. Ther. 302, 1168–1175.
Leach, M.J., Marden, C.M., Miller, A.A., 1986. Pharmacological studies on lamotrigine, a novel potential antiepileptic drug: II. Neurochemical studies on the mechanism of action. Epilepsia 27, 490–497. Lee, T.H., Wang, C.J., Wu, P.C., Buerkle, H., Lin, S.H., Yang, L.C., 2002. The thermal and mechanical anti-hyperalgesic effects of pre- versus post-intrathecal treatment with lamotrigine in a rat model of inflammatory pain. Life Sci. 70, 3039–3047. Lin, J.A., Lee, M.S., Wu, C.T., Yeh, C.C., Lin, S.L., Wen, Z.H., Wong, C.S., 2005. Attenuation of morphine tolerance by intrathecal gabapentin is associated with suppression of morphine-evoked excitatory amino acid release in the rat spinal cord. Brain Res. 1054, 167–173. Lin, J.A., Tsai, R.Y., Lin, Y.T., Lee, M.S., Cherng, C.H., Wong, C.S., Tzeng, J.I., 2008. Amitriptyline pretreatment preserves the antinociceptive effect of morphine in pertussis toxin-treated rats by lowering CSF excitatory amino acid concentrations and reversing the downregulation of glutamate transporters. Brain Res. 1232, 61–69. Lizasoain, I., Leza, J.C., Cuéllar, B., Moro, M.A., Lorenzo, P., 1996. Inhibition of morphine withdrawal by lamotrigine: involvement of nitric oxide. Eur. J. Pharmacol. 299, 41–45. Lopes, L.S., Pereira, S.S., Silva, L.L., Figueiredo, K.A., Moura, B.A., Almeida, F.R., Sousa, F.C., 2009. Antinociceptive effect of topiramate in models of acute pain and diabetic neuropathy in rodents. Life Sci. 84, 105–110. Majeed, N.H., Przewlocka, B., Machelska, H., Przewlocki, R., 1994. Inhibition of nitric oxide synthase attenuates the development of morphine tolerance and dependence in mice Neuropharmacology 33, 189–192. Morgan, M.M., Clayton, C.C., Lane, D.A., 2003. Behavioral evidence linking opioid sensitive GABAergic neurons in the ventrolateral periaqueductal gray to morphine tolerance. Neuroscience 118, 227–232. Nishikawa, K., Tanobe, K., Hinohara, H., Okamoto, T., Saito, S., Goto, F., 2004. Molecular mechanism of morphine tolerance and biological approaches to resolve tolerance. Masui 53, 502–507. Ozek, M., Uresin, Y., Gungor, M., 2003. Comparison of the effects of specific and nonspecific inhibition of nitric oxide synthase on morphine analgesia, tolerance and dependence in mice. Life Sci. 72, 1943–1951. Pasternak, G.W., 2007. When it comes to opiates, just say NO. J. Clin. Invest. 117, 3185–3187. Sahebgharani, M., Hossein-Abad, A.A., Zarrindast, M.R., 2006. On the mechanism of carbamazepine-induced antinociception in the formalin test. Int. J. Neurosci. 116, 1097–1113. Shannon, H.E., Eberle, E.L., Peters, S.C., 2005. Comparison of the effects of anticonvulsant drugs with diverse mechanisms of action in the formalin test in rats. Neuropharmacology 48, 1012–1020. Shuaib, A., Mahmood, R.H., Wishart, T., Kanthan, R., Murabit, M.A., Ijaz, S., Miyashita, H., Howlett, W., 1995. Neuroprotective effects of lamotrigine in global ischemia in gerbils. A histological, in vivo microdialysis and behavioral study. Brain Res. 702, 199–206. Silver, M., Blum, D., Grainger, J., Hammer, A.E., Quessy, S., 2007. Double-blind, placebo-controlled trial of lamotrigine in combination with other medications for neuropathic pain. J. Pain Symptom Manage 34, 446–454. Stoller, D.C., Sim-Selley, L.J., Smith, F.L., 2007. Role of kappa and delta opioid receptors in mediating morphine-induced antinociception in morphine-tolerant infant rats. Brain Res. 1142, 28–36. Tamayo, L., Contreras, E., 1983. A dual action of valproic acid upon morphine analgesia and morphine withdrawal. Pharmacology 26, 297–302.
BR A IN RE S E A RCH 1 2 91 ( 20 0 9 ) 3 2 – 3 9
Taylor, D.A., Fleming, W.W., 2001. Unifying perspectives in the mechanisms underlying the development of tolerance and physical dependence to opioids. J. Pharmacol. Exp. Ther. 297, 1–18. Teoh, H., Fowler, L.J., Bowery, N.G., 1995. Effect of lamotrigine on the electricallyevoked release of endogenous amino acids from slices of dorsal horn of the rat spinal cord. Neuropharmacology 34, 1273–1278. Tjolsen, A., Hole, K., 1997. Animal models of analgesia. In: Dickenson, A.H., Besson, J.M. (Eds.), Pharmacology of Pain. Springer Verlag, Berlin, pp. 1–20. Todorovic, S.M., Rastogi, A.J., Jevtovic-Todorovic, V., 2003. Potent analgesic effects of anticonvulsants on peripheral thermal nociception in rats. Br. J. Pharmacol. 140, 255–260. Tsenov, G., Redkozubova, O., Kubová, H., Mareš, P., 2009. Effects of lamotrigine on cortically-elicited phenomena in adult rats: differences between acute application and late consequences of early postnatal administration. Brain Res. 1258, 65–70. Way, W.L., Fields, H.L., Schumacher, M.A., 2001. Opioid analgesics and antagonists. In: Katzung, B.G. (Ed.), Basic and Clinical Pharmacology. Lange Medical Books/McGraw-Hill companies, USA, pp. 512–532.
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Webb, J., Kamali, F., 1998. Analgesic effects of lamotrigine and phenytoin on cold 76, 357–363. Wiffen, P.J., McQuay, H.J., Edwards, J.E., Moore, R.A., 2005. Gabapentin for acute and chronic pain. Cochrane Database Syst. Rev. 20, 52–54. Yamamoto, T., Ohtori, S., Chiba, T., 2000. Effects of pre-emptively administered nociceptin on the development of thermal hyperalgesia induced by two models of experimental mononeuropathy in the rat. Brain Res. 871, 192–200. Zarrindast, M.R., Dinkub, Z., Homayoun, H., Bakhtiarian, A., 2002. Dopamine receptor mechanisms and morphine tolerance in mice. J. Pysychopharmachol. 16, 261–266. Zhang, G.H., Sweitzer, S.M., 2008. Neonatal morphine enhances nociception and decreases analgesia in young rats. Brain Res. 1199, 82–90. Zullino, D.F., Cottier, A.C., Besson, J., 2002. Topiramate in opiate withdrawal. Prog. Neuropsychopharmacol. Biol. Psychiatry 26, 1221–1223. Zullino, D.F., Krenz, S., Favrat, B., Zimmermann, G., Bertschy, G., Besson, J., 2004. The efficiency of a carbamazepine–mianserin combination scheme in opiate detoxification. Hum. Psychopharmacol. 19, 425–430.
a v a i l a b l e a t w w w. s c i e n c e d i r e c t . c o m
w w w. e l s e v i e r. c o m / l o c a t e / b r a i n r e s
Research Report
Suppressive effects of lamotrigine on the development and expression of tolerance to morphine-induced antinociception in the male mouse Mehdi Saberi a,c,⁎, Behzad Chavooshi b,c a
Department of Pharmacology and Toxicology, Applied Neuroscience Research Center, Faculty of Medicine, Baqiyatallah Medical Sciences University, P.O. Box 19568, Tehran, Iran b Department of Psychology, Faculty of Psychology and Education, University of Tehran, Tehran, Iran c Neuroscience Research Center, Shahid Beheshti University, M.C., Tehran, Iran
A R T I C LE I N FO
AB S T R A C T
Article history:
Previous studies have demonstrated that some anticonvulsant drugs can modulate
Accepted 6 July 2009
tolerance to the opioid analgesia. In the present study, the effects of lamotrigine (LTG) on
Available online 15 July 2009
the development and expression of tolerance to the morphine-induced antinociception were evaluated using tail-flick test. To assess the LTG effects on tolerance development, the
Keywords:
animals received LTG (3, 10 or 30 mg/kg; i.p.), 30-min prior to morphine (50 mg/kg; s.c.)
Lamotrigine
administration during tolerance induction period once daily for 3 days. Also, to evaluate the
Morphine
effects of LTG on tolerance expression, different doses of LTG were administered 30-min
Tolerance
before challenge dose of morphine (4 mg/kg; s.c.) following morphine-induced tolerance. In
Antinociception
each experiment the antinociceptive response to the challenge dose of morphine was
Tail-flick test
evaluated before (on day 1) and after tolerance induction (on day 4) every 30-min till 2 h by
Mouse
tail-flick test. Furthermore, the analgesic effect of various doses of LTG alone or with the challenge dose of morphine was evaluated as well. The results showed that LTG at the doses of 10 and 30 mg/kg could inhibit the development of tolerance. Also, LTG at the dose of 30 mg/kg attenuated the expression of morphine-induced tolerance. LTG alone injection was associated significantly with higher latency period when compared to the control group. Moreover, LTG (10 and 30 mg/kg) significantly enhanced antinociceptive effect of morphine challenge dose in non-tolerant animals. These data indicated that, while LTG can attenuate both development and expression of morphine-induced tolerance, it can enhance morphine-induced antinociception. These effects may have important clinical implications. © 2009 Elsevier B.V. All rights reserved.
1.
Introduction
Opioid drugs are currently the most potent and effective analgesics which are used to relieve moderate to severe pains. However, long-term administration of opioids can alter the
central pain-related systems and lead to the development of tolerance (Ballesteros-Yanez et al., 2008; Hernández et al., 2009). On the other hand, non-opioid drugs are proposed to enhance opioid analgesia and may attenuate their side effects (Way et al., 2001; Lin et al., 2008). Several anticonvulsant drugs
⁎ Corresponding author. Department of Pharmacology and Toxicology, Faculty of Medicine, Baqiyatallah Medical Sciences University, P.O. Box 19568, Tehran, Iran. Fax: +98 21 22830262. E-mail address: [email protected] (M. Saberi). 0006-8993/$ – see front matter © 2009 Elsevier B.V. All rights reserved. doi:10.1016/j.brainres.2009.07.014
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have been shown to treat neuropathic pain conditions because of their effects on voltage- and ligand-gated channels in central pain pathways (Todorovic et al., 2003; Lin et al., 2005). Recent studies suggest that anticonvulsants might decrease opioid consumption either by enhancing opioid analgesia or by suppressing mechanisms of opioid tolerance (Gilron, 2006). For example, carbamazepine (Sahebgharani et al., 2006), phenytoin (Webb and Kamali, 1998), gabapentine (Wiffen et al., 2005), topiramate (Lopes et al., 2009) and vigabatrin (Alvez et al., 1999) have been shown to increase opioids antinociception. Other studies have also revealed that anticonvulsant drugs suppress opioid tolerance (Tamayo and Contreras, 1983; Kosten et al., 1995; Zullino et al., 2002; Zullino et al., 2004; Gilron et al., 2005; Chavooshi et al., 2009). The results of these studies raise the question as to whether such suppressive effect of anticonvulsants is merely a general characteristic of all anticonvulsant drugs or is a specific effect to a certain class of anticonvulsants which may be effective in attenuating morphine-induced tolerance. It has been reported that lamotrigine (LTG) is effective against trigeminal neuralgia refractory to the other treatments, HIV neuropathy, and central post-stroke pains (Backonja, 2002; Silver et al., 2007). In addition, LTG has been shown to induce analgesia in neuropathic pains such as intractable sciatica (Eisenberg et al., 2003) and other models of chronic pains (Hunter et al., 1997; Klamt, 1998; Jensen, 2002; Lee et al., 2002) as well as dynorphin-induced chronic allodynia (Laughlin et al., 2002). However, the antinociceptive effect of LTG in acute pain and in animal models of pain such as tail-flick test has not been fully studied (Laughlin et al., 2002). LTG acts on voltage-dependent Na+ channels to decrease the pre-synaptic release of the excitatory amino acid neurotransmitter-glutamate (Shuaib et al., 1995; Lin et al., 2005; Tsenov et al., 2009) and also can increase the release of GABA, an inhibitory neurotransmitter (Cunningham and Jones, 2000). On the other hand, it has been shown that increment of glutamate or decrements of GABA are involved in morphineinduced tolerance (Asl et al., 2008; Lin et al., 2008). So, it could be suggested that LTG may influence the tolerance to the morphine's analgesia. Additionally, although it has been shown that LTG may represent a useful agent for the treatment of opiate abstinence (Lizasoain et al., 1996), there is no evidence regarding the influence of LTG on the development and expression of morphine-induced tolerance. Therefore, the present study attempted to bring additional evidence to show the effect of LTG on morphine's analgesia and its effects on the development and expression of tolerance to morphine-induced antinociception in the setting of acute nociception through tail-flick assay in mice.
2.
Results
2.1. Experiment (1): Development of tolerance to morphine-induced antinociception The antinociceptive response to a challenge dose of morphine (4 mg/kg; s.c.) for saline and pre-tolerant groups on day 1 was almost similar without any difference at all time set of intervals (Fig. 1A). To assess the morphine tolerance in this
Fig. 1 – The effect of challenge dose (4 mg/kg; s.c.) of morphine, (A) before tolerance induction on day 1 and, (B) following 3 consecutive days administration of saline 10 ml/kg ( ) or morphine 50 mg/kg ( ) as an induction period on day 4. Each point represents the mean ± SEM of percent of maximal possible effect (%MPE) for 7–8 mice. **P < 0.01, ***P < 0.001 compared to saline-treated group.
○
●
study, animals received morphine (50 mg/kg) or saline (10 ml/ kg) once daily for 3 days. Fig. 1B shows the development of tolerance to morphine-induced antinociception tested by challenge dose of morphine (4 mg/kg; s.c.). Two-way ANOVA indicated that the antinociceptive response (the mean of %MPE values) to the challenge dose of morphine on day 4 decreased significantly in morphine-treated animals that received morphine during the induction period in comparison with the saline-treated group [F(1,48) = 69.12, P < 0.0001; Fig. 1B] at all time set intervals. These findings are clearly indicative of the development of tolerance to morphine-induced antinociception following 3 days of morphine treatment. Moreover, the baseline TF latencies were 2 ± 0.24 s and 2.9 ± 0.16 s for saline and tolerant groups on day 4 respectively, and had significant differences when compared by unpaired t-test (P < 0.05).
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2.2. Experiment (2): Effects of LTG on the development of morphine-induced tolerance In this set of experiment, the animals were injected with different doses of LTG (3, 10 or 30 mg/kg; i.p.), 30 min before morphine (50 mg/kg; s.c.) administration once daily for 3 days during the induction period. Our data obtained in Fig. 2 revealed that pretreatment of animals with LTG significantly reduced the development of tolerance to morphine antinociceptive effect in a dose-dependent manner, as indicated by increment of %MPE in LTG treatment groups. However, the lowest dose of LTG (3 mg/kg) had no effect on the development of morphine tolerance. Two-way ANOVA followed by Tukey's post test indicated that in morphine-treated animals that received various doses of LTG prior to morphine during the induction period, the antinociceptive responses to the challenge dose of morphine (4 mg/kg; s.c.) on day 4 significantly increased in comparison to vehicle group that received Tween-80 instead of LTG [F(3,96) = 36.56, P < 0.0001; Fig. 2]. Also, the averages of baseline TF latencies on day 4 were; 2 ± 0.16, 3.3 ± 0.12, 3.1 ± 0.11 and 3.2 ± 0.31 for vehicle, 3, 10 and 30 mg/kg of LTG treatment groups respectively and showed statistically significant difference (P < 0.05). Moreover, in animal which received the highest dose of LTG (30 mg/kg) alone for 3 days there was no additive effect on the antinociceptive response to the challenge dose of morphine on day 4 in comparison to those in control group [F(1,48) = 3.4, P = 0.0617; Fig. 3]. The averages of baseline TF latencies on day 4 were 2 ± 0.33 and 3 ± 0.32 for vehicle and LTG 30 mg/kg, respectively.
2.3. Experiment (3): The effect of LTG on the expression of morphine-induced tolerance
Fig. 3 – The antinociceptive response of single challenge dose of morphine (4 mg/kg) after 3 days co-administration of lamotrigine (LTG) at the dose of 30 mg/kg with saline (solvent of morphine, 10 ml/kg) ( ) or saline alone ( ) on percent of maximal possible effect (%MPE) values at 30-min set intervals on the fourth day. Each point represents the mean ± SEM for 7–8 mice.
●
○
dose prior to challenge dose of morphine (tolerance expression) was sufficient. Thus, the animals received LTG (3, 10 or 30 mg/ kg; i.p.) or vehicle, 30 min before challenge dose of morphine (4 mg/kg) prior to and following morphine-induced tolerance. Two-way ANOVA followed by Tukey's post test indicated that
We next examined whether LTG blockade of morphine tolerance, required daily administration of LTG or if a single
Fig. 2 – The effect of different doses of lamotrigine (LTG) on development of morphine tolerance. Animals received LTG (3, 10 or 30 mg/kg; i.p.) or vehicle (Tween-80, 1%; 10 ml/kg; i.p.), 30 min before morphine (50 mg/kg; s.c.) once daily for 3 days during the induction period. On day 4, the tail-flick latencies were determined after injection of challenge dose of morphine (4 mg/kg; s.c.). Each point represents the mean ± SEM for 7–8 mice. *P < 0.05, ***P < 0.001 compared to saline group.
Fig. 4 – The effect of different doses of lamotrigine (LTG) on the expression of morphine-induced tolerance following 3 days of morphine tolerance induction (50 mg/kg; once daily). Various doses of LTG or vehicle (Tween-80, 1%) were administered 30 min prior to injection of challenge dose of morphine (4 mg/kg; s.c.) on day 4. Each point is the mean ± SEM of percent of maximal possible effect (%MPE) for 7–8 mice. †, * indicate significance in comparison to the morphine-treated (tolerant) and vehicle-treated (non-tolerant) groups, respectively, †††P < 0.05, or ***P < 0.001.
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35
administration of LTG (30 mg/kg) attenuated the expression of morphine tolerance [F(3,96) = 73.41, P < 0.0001; Fig. 4] at all time set intervals. The averages of baseline TF latencies on day 4 were; 2 ± 0.19, 2.1 ± 0.22, 3.1 ± 0.15 and 2.7 ± 0.34 for vehicle, 3, 10 and 30 mg/kg of LTG treatment groups respectively and showed statistically significant difference (P < 0.05).
2.4. Experiment (4): The antinociceptive effects of LTG and its combination with morphine To determine the effect of LTG on antinociceptive response of morphine, tail-flick tests were done for each animal at 0.5, 1, 1.5 and 2 h after single injection of LTG (3, 10 or 30 mg/kg; i.p.). Data analysis indicated that LTG (30 mg/kg) could significantly increase the %MPE when compared to those of control group [F (3,96) = 9.38, P < 0.0001; Figs. 5A, B]. In addition, to evaluate the effects of LTG on morphineinduced antinociception, the animals received various doses of LTG (3, 10 or 30 mg/kg; i.p.), 30 min before morphine (4 mg/ kg; s.c.) injection. Two-way ANOVA indicated that the coadministration of LTG (30 mg/kg) with morphine (4 mg/kg) significantly increased the %MPE in comparison to morphine alone treated group [F(3,96) = 10.58, P < 0.0001; Figs. 6A, B].
Fig. 6 – Effects of the different doses of lamotrigine (LTG) or vehicle (Tween-80, 1%) in combination with morphine (Mor) in (A) the average of tail-flick latencies and, (B) the percent of maximal possible effect (%MPE). The animals received LTG (3, 10 or 30 mg/kg), 30 min before morphine administration. Each point is the mean ± SEM for 7–8 mice. **P < 0.01; ***P < 0.001 compared to morphine-treated group.
3.
Fig. 5 – The antinociceptive effects of the different doses of lamotrigine (LTG) alone or vehicle (Tween-80, 1%) in (A) the average of tail-flick latencies and, (B) the percent of maximal possible effect (%MPE). Each point is the mean ± SEM for 7–8 mice. ***P < 0.001 compared to vehicle-treated group.
Discussion
The major findings of the present study were: (1) LTG attenuated the development of morphine-induced tolerance, (2) LTG attenuated the expression of tolerance to the antinociceptive effect of morphine, (3) LTG enhanced the antinociceptive effect of morphine in a dose-dependent manner and (4) LTG exhibited antinociceptive effect in the tail-flick test as an acute pain model. Although, the base line latencies for the saline groups were lower than other treated groups before challenge dose of morphine administration (because of the effects of treatments till day 4), the data were normalized using %MPEs. One of the major problems associated with the chronic use of morphine is tolerance. Repeated uses of morphine to relieve pain often cause patients to develop increasing resistance to
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the effects of the drugs, so that progressively higher doses are require to achieve the same analgesic effects (Yamamoto et al., 2000; Stoller et al., 2007; Zhang and Sweitzer, 2008). In the present study, we showed that LTG pretreatment can inhibit the development of morphine tolerance in a dosedependent manner. Our results are in agreement with the data from previous studies suggesting that anticonvulsant drugs attenuate opioid tolerance (Tamayo and Contreras, 1983; Kosten et al., 1995; Zullino et al., 2002; Zullino et al., 2004; Chavooshi et al., 2009). Given that different analgesic mechanism(s) for LTG and morphine and those underlying opioid tolerance are still unclear, understanding the interaction between these two drugs becomes difficult. One common link between morphine-induced tolerance and LTG analgesia is the modulation of glutamate receptors (Nishikawa et al., 2004; Lin et al., 2005; Lin et al., 2008). Also, previous studies showed that GABAergic system could play a role in the progression of morphine tolerance (Morgan et al., 2003; Asl et al., 2008). On the other hand, it showed that LTG increases GABA release (Cunningham and Jones, 2000). Hence, it could be concluded that increase of GABA release by LTG plays an inhibitory role for the development of morphine tolerance. Moreover, recent evidence suggests that nitric acid (NO), an endogenous molecule implicated in the regulation of a number of physiologic and pathogenic processes, is involved in the development of morphine tolerance (Ozek et al., 2003; Heinzen and Pollack, 2004). It seems that NO production via activation of N-methyl-D-aspartate (NMDA) receptors results in morphine tolerance (Pasternak, 2007). There are many reports showing that blockade of nitric oxide synthase (NOS) results in attenuation of morphine tolerance as well (Kolesnikov et al., 1993; Majeed et al., 1994; Dambisya and Lee, 1996; Homayoun et al., 2002). Lizasoain et al. (1996) showed that nitric oxide is involved in the suppression of morphine withdrawal symptoms during LTG treatment. Thus, it could be suggested that NO might be involved in attenuation of morphine tolerance by LTG. However, further studies are needed to confirm these aforementioned hypotheses. It has been previously reported that the development and expression of morphine-induced tolerance are distinct phases (Taylor and Fleming, 2001). Our results indicate that LTG can attenuate the expression of morphine's tolerance. Based on the analgesic effect of LTG alone and also its additive analgesic effect on morphine's challenge dose, it seems that the expression is more attenuated by additive effect of LTG than reversal of tolerance. In terms of its clinical effects, LTG especially is effective against trigeminal neuralgia, painful peripheral neuropathy, and post-stroke pain (Jensen, 2002). Animal experiments have shown the analgesic effects of LTG in painful conditions, such as dynorphin-induced chronic allodynia and formalin (Laughlin et al., 2002, Shannon et al., 2005) and cold-pressor tests (Webb and Kamali, 1998) as well as chronic constriction injury and hyperalgesia models in rats (Hunter et al., 1997; Klamt, 1998; Klamt and Posner, 1999). The results of this study showed that LTG had an important antinociceptive effect in acute condition. In contrast, Laughlin et al. (2002) have shown that LTG is ineffective in hotplate test. However hotplate test consists of stimulating the four limbs and even the tail of the animal simultaneously (Le Bars
et al., 2001). Such heterotopic stimuli involving large body areas undoubtedly trigger diffuse inhibitory controls that are likely to disturb the observed responses (Tjolsen and Hole, 1997). Several studies have indicated the involvement of the voltage activated sodium channels in LTG-induced antinociception via preventing the release of excitatory neurotransmitters (Leach et al., 1986; Teoh et al., 1995). Also, LTG inhibits sustained repetitive neuronal firing (Cheung et al., 1992) through increase of GABA release (Kuzniecky et al., 2002; Finnerup et al., 2002). These properties of LTG are suggestive of a drug having antinociceptive action. In the other set of our experiments, the effect of LTG on antinociceptive response of morphine was evaluated. We show that LTG enhances morphine's antinociceptive effects in tail-flick test. Our results are in agreement with the data from previous studies suggesting that the combination of morphine and LTG produced a dose-related antinociceptive effect, in rats in a formalin test (Arguelles et al., 2002). As a result, coadministration of drugs such as LTG with morphine which can produce therapeutic analgesia with lower dose of morphine would be of great clinical implication. In conclusion, based on the aforementioned findings and the observed analgesic effects of LTG alone as well as its ability to attenuate the development and expression of morphine tolerance, co-administration of LTG and morphine may be worthwhile for clinical applications.
4.
Experimental procedures
4.1.
Animals
One hundred and twenty adult male albino NMRI mice (Pasteur Institute, Iran) weighing 20–25 g were used in these experiments. They were kept 8–10 per cage (45 × 30 × 15 cm) at a room controlled temperature (23 ± 1 °C) and maintained on a 12-h light/dark cycle (light on 07:00 h) with free access to the standard rodent breeding diet and tap water. Each animal was used only once and killed immediately after the experiment. All experiments were performed in accordance with the Guide for the Care and Use of Laboratory Animals (National Institutes of Health Publication No. 80–23, revised 1996) and were approved by the Research and Ethics Committee of Tehran University. 4.2.
Drugs preparation
Morphine sulphate (Temad Co, Iran) dissolved in saline and lamotrigine (Baakhtar Co, Iran) were suspended in 1% solution of Tween-80 (Sigma, USA) in saline. The LTG and morphine were prepared immediately before use and injected intraperitoneally (i.p.) and subcutaneously (s.c.) in a volume of 10 ml/kg, respectively. 4.3.
Assessment of morphine antinociception
Nociception was assessed with the tail-flick apparatus (D'amour and Smith, 1941). Before the test, animals were allowed to adapt to the conditions of the laboratory room for at least 1 h. Moreover, animals were alternatively
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allocated in their restrainers for 1 min each 15 min before the test in order to attenuate the stress that has been shown to produce antinociception. Restrained animals were placed on the tail-flick apparatus (type 812, Hugo Sachs Elektronik, Germany), a noxious beam of light was focused on the tail about 4 cm from the tip, and tail-flick latency was recorded automatically. Tail-flick latency (TFL) is a spinal response and, therefore, TFL is a measurement of pain threshold at the spinal level. The intensity of the radiant heat source was adjusted to yield baseline latencies between 1.8 and 4 s, this intensity was never changed and any animal whose baseline latency was outside the pre-established limits was excluded from the experiments. In order to minimize injury in the animals, a cut-off time of 8 s was used. Baseline latency was assessed in duplicate with 30-min intervals and recorded as an average of TFL time. TFL sec are expressed as percentage of maximal possible effect (%MPE) which was calculated from the following formula: kMPE=
4.4.
Post drug latency ðsecÞ Baseline latency ðsecÞ 100: Cut off value ðsecÞ Baseline latency ðsecÞ
Experimental protocols
4.4.1. Experiment (1): Development of tolerance to morphine-induced antinociception Tolerance induction was begun on day 1, 4 h after challenge dose of morphine (4 mg/kg; s.c.) by administration of morphine (50 mg/kg; s.c.) or saline (10 ml/kg; as control) once daily for 3 days as has been previously described (Zarrindast et al., 2002). The antinociceptive response to a challenge dose of morphine (4 mg/kg; s.c.) was determined by tail-flick test at 30-min intervals (0.5, 1, 1.5 and 2 h) on day 1 and day 4 for tolerance evaluation (n = 7–8 in each group). The challenge dose of morphine was selected as already described by Hienzen and Pollack (2004). 4.4.2. Experiment (2): Effects of LTG on the development of morphine-induced tolerance In these experiments, to evaluate the effects of LTG on the induction of morphine's tolerance, animals (n = 7–8) received various doses of LTG (3, 10 or 30 mg/kg; i.p.), 30 min before morphine (50 mg/kg; s.c.) or vehicle (Tween-80, 1%) once daily for 3 consecutive days. The effect of the challenge dose of morphine (4 mg/kg; s.c.) was tested on day 1 prior to and on day 4 following the induction period of morphine tolerance at different time set intervals as cited above. The doses of LTG were selected based on previous study that evaluated the antinociceptive action of LTG, which is lower than those used as anticonvulsants in experimental models in mice (Christensen et al., 2001). Also, the animals in separated groups (n = 7–8), were treated with high dose of LTG or saline alone for 3 days and then the response to challenge dose of morphine was only tested on the 4th day (test day) to determine whether there are carryover interactions between repeated LTG administration and subsequent morphine testing.
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4.4.3. Experiment (3): The effect of LTG on the expression of morphine-induced tolerance In this set of experiments, to assess the effects of LTG on the expression of morphine-induced tolerance, animals (n = 7–8) received different doses of LTG (3, 10 or 30 mg/kg) or vehicle (Tween-80, 1%), 30 min before challenge dose of morphine (4 mg/kg) following morphine-induced tolerance. The antinociceptive responses to the challenge dose of morphine for each animal were determined by tail-flick test on day 4 (post- tolerance induction) at different time set intervals, as described in section 4.4.1. 4.4.4. Experiment (4): The antinociceptive effects of LTG and its combination with morphine The antinociceptive effects of various single doses of LTG (3, 10 or 30 mg/kg) alone or vehicle (Tween-80, 1%) were determined at different time set intervals (0.5, 1, 1.5 and 2 h), 30 min post-injection. Also, the analgesic response of LTG in combination with morphine (4 mg/kg; s.c.) was evaluated as cited above. The animals (n = 7–8) received either LTG or vehicle (Tween-80, 1%), 30 min prior to morphine injection. 4.5.
Statistical analysis
The results obtained are expressed as mean ± SEM (standard error of mean). The mean MPEs in all groups were subjected to one-way and/or two-way ANOVA followed by Tukey's post test for multiple comparisons between groups, as needed. Data were processed by commercially available software GraphPad Prism® 5.0. P-values less than 0.05 were considered to be statistically significant.
Acknowledgments This work was supported by the Neuroscience Research Center, Shahid Beheshti University, M.C., Tehran, Iran. We thank Dr. Abolhassan Ahmadiani for his excellent technical assistance. REFERENCES
Alvez, D.A., Castro-Costa, C., Charvalho, A., Santos, F., Silveira, D., 1999. Possible analgesic effect of vigabatrin in animal experimental chronic neuropathic pain. Arq. Neuropsiquiatr. 57, 916–920. Arguelles, C.F., Torres-Lopez, J.E., Granados-Soto, V., 2002. Peripheral antinociceptive action of morphine and the synergistic interaction with lamotrigine. Anesthesiology 96, 921–925. Asl, B.H., Hassanzadeh, K., Khezri, E., Mohammadi, S., 2008. Evaluation the effects of dextromethorphan and midazolam on morphine induced tolerance and dependence in mice. Pak. J. Biol. Sci. 11, 1690–1695. Backonja, M.M., 2002. Use of anticonvulsants for treatment of neuropathic pain. Neurology 591, 4–17. Ballesteros-Yanez, I., Ambrosio, E., Pérez, J., Torres, I., Miguéns, M., García Lecumberri, C., DeFelipe, J., 2008. Morphine selfadministration effects on the structure of cortical pyramidal cells in addiction-resistant rats. Brain Res. 1230, 61–72. Chavooshi, B., Saberi, M., Tehrani, S.P., Bakhtiarian, A., Ahmadiani, A., Haghparast, A., 2009. Vigabatrin attenuates the
38
BR A IN RE S EA RCH 1 2 91 ( 20 0 9 ) 3 2 – 39
development and expression of tolerance to morphine-induced antinociception in mice. Pharmacol. Biochem. Behav. 93, 155–159. Cheung, H., Kamp, D., Harris, E., 1992. An in vitro investigation of the action of lamotrigine on neuronal voltage-activated sodium channels. Epilepsy Res. 13, 107–112. Christensen, D., Gautron, M., Guilbaud, G., Kayser, V., 2001. Effect of gabapentin and lamotrigine on mechanical allodynia-like behaviour in a rat model of trigeminal neuropathic pain. Pain 93, 147–153. Cunningham, M.O., Jones, R.S.G., 2000. The anticonvulsant, lamotrigine decreases spontaneous glutamate release but increases spontaneous GABA release in the rat entorhinal cortex in vitro. Neuropharmacology 39, 2139–2146. Dambisya, Y.M., Lee, T.L., 1996. Role of nitric oxide in the induction and expression of morphine tolerance and dependence in mice. Br. J. Pharmacol. 117, 914–918. D'amour, F.E., Smith, D.L., 1941. A method for determining loss of pain sensation. J. Pharmacol. Exp. Ther. 72, 74–79. Eisenberg, E., Damunni, G., Hoffer, E., Baum, Y., Krivoy, N., 2003. Lamotrigine for intractable sciatica: correlation between dose, plasma concentration and analgesia. Eur. J. Pain 7, 485–491. Finnerup, N.B., Gottrup, H., Jensen, T.S., 2002. Anticonvulsants in central pain. Expert. Opin. Pharmacother 3, 1411–1420. Gilron, I., 2006. The role of anticonvulsant drugs in postoperative pain management: a bench-to-bed-side perspective. Can. J. Anesth. 53, 562–571. Gilron, I., Bailey, J.M., Tu, D., Holden, R.R., Weaver, D.F., Houlden, R.L., 2005. Morphine, gabapentin or their combination for neuropathic pain. N. Engl. J. MED. 352, 1324–1334. Heinzen, E.L., Pollack, G.M., 2004. The development of morphine antinociceptive tolerance in nitric oxide synthase-deficient mice. Biochemi. Pharmacol. 67, 735–741. Hernández, L., Romero, A., Almela, P., García-Nogales, P., Laorden, M.L., Puig, M.M., 2009. Tolerance to the antinociceptive effects of peripherally administered opioids: expression of β-arrestins. Brain Res. 1248, 31–39. Homayoun, H., Khavandgar, S., Namiranian, K., Dehpour, A.R., 2002. The effect of cyclosporin A on morphine tolerance and dependence: involvement of larginine/nitric oxide pathway. Eur. J. Pharmacol. 452, 67–75. Hunter, J.C., Gogas, K.R., Hedley, L.R., Jacobson, L.O., Kassotakis, L., Thompson, J., Fontana, D.J., 1997. The effect of novel anti-epileptic drugs in rat experimental models of acute and chronic pain. Eur. J. Pharmacol. 324, 153–160. Jensen, T.S., 2002. Anticonvulsants in neuropathic pain: rationale and clinical evidence. Eur. J. Pain 6, 61–68. Klamt, J.G., 1998. Effects of intrathecally administered lamotrigine, a glutamate release inhibitor, on short- and long-term models of hyperalgesia in rats. Anesthesiology 88, 487–494. Klamt, J.G., Posner, J., 1999. Effects of lamotrigine on pain-induced chemo somatosensory evoked potentials. Anaesthesia 54, 774–777. Kolesnikov, Y.A., Pick, C.G., Ciszewska, G., Pasternak, G.W., 1993. Blockade of tolerance to morphine but not to kappa opioids by a nitric oxide synthase inhibitor. Proc. Natl. Acad. Sci. U. S. A. 90, 5162–5166. Kosten, T.A., DeCaprio, J.L., Rosen, M.I., 1995. The severity of naloxan-percipitate opiate withdrawal is attenuated by felbamate, a possible glycine antagonist Neuropsychopharmachology 13, 23–33. Kuzniecky, R., Ho, S., Pan, J., Martin, R., Gilliam, F., Faught, E., Hetherington, H., 2002. Modulation of cerebral GABA by topiramate, lamotrigine, and abapentin in healthy adults. Neurology 58, 368–372. Laughlin, T.M., Tram, K.V., Wilcox, G.L., Birnbaum, A.K., 2002. Comparison of acute, prolonged, and chronic nociception. J. Pharmacol. Exp. Ther. 302, 1168–1175.
Leach, M.J., Marden, C.M., Miller, A.A., 1986. Pharmacological studies on lamotrigine, a novel potential antiepileptic drug: II. Neurochemical studies on the mechanism of action. Epilepsia 27, 490–497. Lee, T.H., Wang, C.J., Wu, P.C., Buerkle, H., Lin, S.H., Yang, L.C., 2002. The thermal and mechanical anti-hyperalgesic effects of pre- versus post-intrathecal treatment with lamotrigine in a rat model of inflammatory pain. Life Sci. 70, 3039–3047. Lin, J.A., Lee, M.S., Wu, C.T., Yeh, C.C., Lin, S.L., Wen, Z.H., Wong, C.S., 2005. Attenuation of morphine tolerance by intrathecal gabapentin is associated with suppression of morphine-evoked excitatory amino acid release in the rat spinal cord. Brain Res. 1054, 167–173. Lin, J.A., Tsai, R.Y., Lin, Y.T., Lee, M.S., Cherng, C.H., Wong, C.S., Tzeng, J.I., 2008. Amitriptyline pretreatment preserves the antinociceptive effect of morphine in pertussis toxin-treated rats by lowering CSF excitatory amino acid concentrations and reversing the downregulation of glutamate transporters. Brain Res. 1232, 61–69. Lizasoain, I., Leza, J.C., Cuéllar, B., Moro, M.A., Lorenzo, P., 1996. Inhibition of morphine withdrawal by lamotrigine: involvement of nitric oxide. Eur. J. Pharmacol. 299, 41–45. Lopes, L.S., Pereira, S.S., Silva, L.L., Figueiredo, K.A., Moura, B.A., Almeida, F.R., Sousa, F.C., 2009. Antinociceptive effect of topiramate in models of acute pain and diabetic neuropathy in rodents. Life Sci. 84, 105–110. Majeed, N.H., Przewlocka, B., Machelska, H., Przewlocki, R., 1994. Inhibition of nitric oxide synthase attenuates the development of morphine tolerance and dependence in mice Neuropharmacology 33, 189–192. Morgan, M.M., Clayton, C.C., Lane, D.A., 2003. Behavioral evidence linking opioid sensitive GABAergic neurons in the ventrolateral periaqueductal gray to morphine tolerance. Neuroscience 118, 227–232. Nishikawa, K., Tanobe, K., Hinohara, H., Okamoto, T., Saito, S., Goto, F., 2004. Molecular mechanism of morphine tolerance and biological approaches to resolve tolerance. Masui 53, 502–507. Ozek, M., Uresin, Y., Gungor, M., 2003. Comparison of the effects of specific and nonspecific inhibition of nitric oxide synthase on morphine analgesia, tolerance and dependence in mice. Life Sci. 72, 1943–1951. Pasternak, G.W., 2007. When it comes to opiates, just say NO. J. Clin. Invest. 117, 3185–3187. Sahebgharani, M., Hossein-Abad, A.A., Zarrindast, M.R., 2006. On the mechanism of carbamazepine-induced antinociception in the formalin test. Int. J. Neurosci. 116, 1097–1113. Shannon, H.E., Eberle, E.L., Peters, S.C., 2005. Comparison of the effects of anticonvulsant drugs with diverse mechanisms of action in the formalin test in rats. Neuropharmacology 48, 1012–1020. Shuaib, A., Mahmood, R.H., Wishart, T., Kanthan, R., Murabit, M.A., Ijaz, S., Miyashita, H., Howlett, W., 1995. Neuroprotective effects of lamotrigine in global ischemia in gerbils. A histological, in vivo microdialysis and behavioral study. Brain Res. 702, 199–206. Silver, M., Blum, D., Grainger, J., Hammer, A.E., Quessy, S., 2007. Double-blind, placebo-controlled trial of lamotrigine in combination with other medications for neuropathic pain. J. Pain Symptom Manage 34, 446–454. Stoller, D.C., Sim-Selley, L.J., Smith, F.L., 2007. Role of kappa and delta opioid receptors in mediating morphine-induced antinociception in morphine-tolerant infant rats. Brain Res. 1142, 28–36. Tamayo, L., Contreras, E., 1983. A dual action of valproic acid upon morphine analgesia and morphine withdrawal. Pharmacology 26, 297–302.
BR A IN RE S E A RCH 1 2 91 ( 20 0 9 ) 3 2 – 3 9
Taylor, D.A., Fleming, W.W., 2001. Unifying perspectives in the mechanisms underlying the development of tolerance and physical dependence to opioids. J. Pharmacol. Exp. Ther. 297, 1–18. Teoh, H., Fowler, L.J., Bowery, N.G., 1995. Effect of lamotrigine on the electricallyevoked release of endogenous amino acids from slices of dorsal horn of the rat spinal cord. Neuropharmacology 34, 1273–1278. Tjolsen, A., Hole, K., 1997. Animal models of analgesia. In: Dickenson, A.H., Besson, J.M. (Eds.), Pharmacology of Pain. Springer Verlag, Berlin, pp. 1–20. Todorovic, S.M., Rastogi, A.J., Jevtovic-Todorovic, V., 2003. Potent analgesic effects of anticonvulsants on peripheral thermal nociception in rats. Br. J. Pharmacol. 140, 255–260. Tsenov, G., Redkozubova, O., Kubová, H., Mareš, P., 2009. Effects of lamotrigine on cortically-elicited phenomena in adult rats: differences between acute application and late consequences of early postnatal administration. Brain Res. 1258, 65–70. Way, W.L., Fields, H.L., Schumacher, M.A., 2001. Opioid analgesics and antagonists. In: Katzung, B.G. (Ed.), Basic and Clinical Pharmacology. Lange Medical Books/McGraw-Hill companies, USA, pp. 512–532.
39
Webb, J., Kamali, F., 1998. Analgesic effects of lamotrigine and phenytoin on cold 76, 357–363. Wiffen, P.J., McQuay, H.J., Edwards, J.E., Moore, R.A., 2005. Gabapentin for acute and chronic pain. Cochrane Database Syst. Rev. 20, 52–54. Yamamoto, T., Ohtori, S., Chiba, T., 2000. Effects of pre-emptively administered nociceptin on the development of thermal hyperalgesia induced by two models of experimental mononeuropathy in the rat. Brain Res. 871, 192–200. Zarrindast, M.R., Dinkub, Z., Homayoun, H., Bakhtiarian, A., 2002. Dopamine receptor mechanisms and morphine tolerance in mice. J. Pysychopharmachol. 16, 261–266. Zhang, G.H., Sweitzer, S.M., 2008. Neonatal morphine enhances nociception and decreases analgesia in young rats. Brain Res. 1199, 82–90. Zullino, D.F., Cottier, A.C., Besson, J., 2002. Topiramate in opiate withdrawal. Prog. Neuropsychopharmacol. Biol. Psychiatry 26, 1221–1223. Zullino, D.F., Krenz, S., Favrat, B., Zimmermann, G., Bertschy, G., Besson, J., 2004. The efficiency of a carbamazepine–mianserin combination scheme in opiate detoxification. Hum. Psychopharmacol. 19, 425–430.