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Inhibition of respiratory burst in mice macrophages by opioid peptide [D-ALA2]methionine enkephalinamide
SALMON CALCITONIN POTENCIATES ANALGESIA INDUCED BY DELTA AND KAPPA OPIOID AGONISTS. C. Goic0echea, M.J. Alfaro, M.J. Ormaz&bal, M.I. Martfn. Dpto Farmacologfa. Fac Medicina. U, Complutense de Madrid. Madrid 28040. SPAIN Salmon calcitonin is a polypeptide hormone involved in calcium homeostasis. It has been proved that the hormone also posesses an analgesic effect, altough the mechanism involved in this analgesia still not fully clarified. In this work we studied, using the writhing test in mice, the effect of salmon calcitonin (S-CT) in the antinociceptive effect of t w o opioid agonist, U50,488H (U50) (a kappa agonist) and [DPen2,D-Pen 5] enkephalin (DPEN)(a delta agonist). When a subanalgesic dose of S-CT (2.5 IU/kg, i.p.) was administered 30 minutes before the agonists, in both cases their analgesic effect was significantly increased. U50(2,5) U50(5) U50(10) mg/kg Control 100 3.3_+6.1 19.8+10.8 66,2+_7 S-CT 21 _+7 32_+4.7** 50_+4.7** 79.4_+4.6 DPEN(1 50) DPEN(300) DPEN(600) nM Control 100 13.6_+5.1 19.3±5.7 48.6_+ 5.7 S-CT 2 1 ± 7 5 3 . 6 + 1 0 " * 58.7±6.3** 73.9_+2.5 The values indicate the % of inhibition ± sem (n_> 11 ) and * * represents a significant difference v s control values (p < 0.05). This result confirms that the analgesic effect induced by S-CT is related with the opioid system and that the hormone potentiates the analgesic effect of delta and kappa agonists. This work was partially supported by Rhfne-Poulenc-Rorer s°a.
TRAMADOL CONTROLLED RELEASE FORMULA VS. STANDARD FORMULATION: COMPARISON OF ANALGESIC EFFECTS T. Hummel. S. Roscher, and G. Kobal Dept. of Exp. and Clin. Pharmacology and Toxicology, University of Erlangen-N0rnberg, Krankenhausstr. 9, 91054 Erlangen, Germany The study aimed to test the anal- 2. gesic properties of the controlled release formulation of tramadol; it 0, was performed by means of an ~v] experimental pain model based on -2. chemo-somatosensory event-related potentials (CSSERP) in re- -4, sponse to painful chemical stimuli applied to the nasal mucosa. -6 Twenty healthy volunteers parti6 k g d g 16 12 [hours alter administration] cipated in the experiments following a double-blind, 3-fold crossT100 - 8 - - TCR100 .-,I,- TCR150 over design. Each of the 3 medications (tramadol 100 mg [T100], tramadol controlled release 100and Amplitude N1 at Cz: Means, SEM, 150 mg [TCR100, TCR150]) was n=2O. Differences between data obadministered orally to the fasted tained after and before drug adminissubjects. Experiments were divided tration (*: factor "drug", p<0.05). into five sessions (before, 2, 4, 6, and 12 h after drug administration). In addition to assessment of CSSERP, subjects rated the intensity Of painful stimuli. Unspecific .drug effects were monitored by means of frequency analyses of the spontaneous EEG, ratings of side effects, and the performance in a video game. The significant reduction of amplitude N1 at central recording positions indicated that TCR150 was the most effective analgesic 12 h after administration; TCR100 took the medium position between TCR150 and T100 (Fig. 1).
THE ANTINOClCEPTIVE EFFECT OF A LEUKOTRIENE RECEPTOR ANTAGONIST AND A DUAL INHIBITOR OF ARACHIDONIC ACID BY TWO TESTS IN MICE. ~.G~J~.N. Gacar, N. Erciyes,N.i. Kalyoncu Deparment of Pharmacology, School of Medicine, Karadeniz Technical University,61080 Trabzon,Turkey. Metabolites of arachidonate cyclo-oxygenase are important of inflammatory mediators and inhibition of their synthesis by nonsteroidal anti-inflammatorydrugs ameliorate the primary symptoms of inflammation. Leukotrienes, which are products of arachidonate 5- lypoxygenase together with prostaglandins, have been detected in the inflammatory responses. Leukotriene B4 (LTB4) is a potent chemotactic and chemocinetic agent for neutrophils and causes hyperalgesia. Peptidolipid leukotrienes (LTC4, LTD4, LTE4) are involved in immediate hypersensitivity responses and cause potent smooth muscle contractions. They also increase vascular permeability and may contribute to inflammatory oedema. We decided to compare the antinoceptiveeffect of leukotriene D4 receptor antagonist L-648, 051 (4-[3-(4-acetyl-3hydroxy -2- proply- phenoxy- propylsulfonyl]-oxo-benzenebutanoicacid) and a dual inhibitor of lypoxygenase and cyclooxygenase BW-7550 (3amino-l-(3-trifluoromethylphenyl)-2-pyrazolinehydrochloride)by using the hot-plate test (a cutaneous thermal response) and the writhing test (a visceral chemical test). And, in addition, the analgesic influence of these drugs on the mice pretreated with a subanalgesic dose of morphine. In the hot-plate test, L-648,051 (5mg/kg, i.p.) and BW-7550 (10 mg/kg, Lp.) did not induce significant changes in the nociceptive threshold. However, when a subanalgesic dose of morphine was administered 30 minutes before these drugs at the same doses, their antinociceptive effect increased significantly. In the writhing test, the number of streches, when compared with he control group, was decreased by L-648,051, but not by BW-7550. These findings indicate that L-648,051 and BW-755C have little effect in the control of pain and this effect varies according to the nature of stimuli. In addition, they also suggest the presence of a relationship between the lypoxygenase system and the opioid system. This means we could recude the dose of morphine to produce an analgesic effect and thus, possibly, the side effects could be decreased.
INHIBITION OF RESPIRATORY BURST IN MICE MACROPHAGES BY OPIOID PEPTIDE [D-ALA2 ]METHIONINE ENKEPHALINAMIDE A.A.Koshkin, S.V.Zaitscv A.N.Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow 119899, Russia.
This research was supported by Mundipharma, Limburg, Germany.
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The respiratory burst induced by phorbol mydstate acetate in mice macrophages was inhibited by 10-13 10-15 M of opioid peptide [D-Ala2]methionine enkephalinamide (DAMEA). The effect dissappeared at concentrations above and below this range. The inhibition approached 50% and was statistically significant (p<0.001). An increase in the time of incubation of the opioid with cells results in the shift of tile maximal effect to the lower concentrations of opioid (from about 10-13 to 5"10 -15 M) and decrease in the value of the effect. The antagonist of opioid receptors naloxone in 10-7 M abolishes the i~khibitory effect of 10-14 M DAMEA (10 rain incubation) on respiratory burst: the effect decreases from 40+/-7% to 6+/-2% (lrtean +/- SEM) in the presence of naloxone. Treatment with naloxone alone had no significant effect on respiratory burst. Aminoacids constituting DAMEA do not have any effect on tile respiratory burst when added in 10-14 M. These data indicate that hahibitory effect of DAMEA is mediated by specific opioid receptors.
TRAMADOL CONTROLLED RELEASE FORMULA VS. STANDARD FORMULATION: COMPARISON OF ANALGESIC EFFECTS T. Hummel. S. Roscher, and G. Kobal Dept. of Exp. and Clin. Pharmacology and Toxicology, University of Erlangen-N0rnberg, Krankenhausstr. 9, 91054 Erlangen, Germany The study aimed to test the anal- 2. gesic properties of the controlled release formulation of tramadol; it 0, was performed by means of an ~v] experimental pain model based on -2. chemo-somatosensory event-related potentials (CSSERP) in re- -4, sponse to painful chemical stimuli applied to the nasal mucosa. -6 Twenty healthy volunteers parti6 k g d g 16 12 [hours alter administration] cipated in the experiments following a double-blind, 3-fold crossT100 - 8 - - TCR100 .-,I,- TCR150 over design. Each of the 3 medications (tramadol 100 mg [T100], tramadol controlled release 100and Amplitude N1 at Cz: Means, SEM, 150 mg [TCR100, TCR150]) was n=2O. Differences between data obadministered orally to the fasted tained after and before drug adminissubjects. Experiments were divided tration (*: factor "drug", p<0.05). into five sessions (before, 2, 4, 6, and 12 h after drug administration). In addition to assessment of CSSERP, subjects rated the intensity Of painful stimuli. Unspecific .drug effects were monitored by means of frequency analyses of the spontaneous EEG, ratings of side effects, and the performance in a video game. The significant reduction of amplitude N1 at central recording positions indicated that TCR150 was the most effective analgesic 12 h after administration; TCR100 took the medium position between TCR150 and T100 (Fig. 1).
THE ANTINOClCEPTIVE EFFECT OF A LEUKOTRIENE RECEPTOR ANTAGONIST AND A DUAL INHIBITOR OF ARACHIDONIC ACID BY TWO TESTS IN MICE. ~.G~J~.N. Gacar, N. Erciyes,N.i. Kalyoncu Deparment of Pharmacology, School of Medicine, Karadeniz Technical University,61080 Trabzon,Turkey. Metabolites of arachidonate cyclo-oxygenase are important of inflammatory mediators and inhibition of their synthesis by nonsteroidal anti-inflammatorydrugs ameliorate the primary symptoms of inflammation. Leukotrienes, which are products of arachidonate 5- lypoxygenase together with prostaglandins, have been detected in the inflammatory responses. Leukotriene B4 (LTB4) is a potent chemotactic and chemocinetic agent for neutrophils and causes hyperalgesia. Peptidolipid leukotrienes (LTC4, LTD4, LTE4) are involved in immediate hypersensitivity responses and cause potent smooth muscle contractions. They also increase vascular permeability and may contribute to inflammatory oedema. We decided to compare the antinoceptiveeffect of leukotriene D4 receptor antagonist L-648, 051 (4-[3-(4-acetyl-3hydroxy -2- proply- phenoxy- propylsulfonyl]-oxo-benzenebutanoicacid) and a dual inhibitor of lypoxygenase and cyclooxygenase BW-7550 (3amino-l-(3-trifluoromethylphenyl)-2-pyrazolinehydrochloride)by using the hot-plate test (a cutaneous thermal response) and the writhing test (a visceral chemical test). And, in addition, the analgesic influence of these drugs on the mice pretreated with a subanalgesic dose of morphine. In the hot-plate test, L-648,051 (5mg/kg, i.p.) and BW-7550 (10 mg/kg, Lp.) did not induce significant changes in the nociceptive threshold. However, when a subanalgesic dose of morphine was administered 30 minutes before these drugs at the same doses, their antinociceptive effect increased significantly. In the writhing test, the number of streches, when compared with he control group, was decreased by L-648,051, but not by BW-7550. These findings indicate that L-648,051 and BW-755C have little effect in the control of pain and this effect varies according to the nature of stimuli. In addition, they also suggest the presence of a relationship between the lypoxygenase system and the opioid system. This means we could recude the dose of morphine to produce an analgesic effect and thus, possibly, the side effects could be decreased.
INHIBITION OF RESPIRATORY BURST IN MICE MACROPHAGES BY OPIOID PEPTIDE [D-ALA2 ]METHIONINE ENKEPHALINAMIDE A.A.Koshkin, S.V.Zaitscv A.N.Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow 119899, Russia.
This research was supported by Mundipharma, Limburg, Germany.
--118--
The respiratory burst induced by phorbol mydstate acetate in mice macrophages was inhibited by 10-13 10-15 M of opioid peptide [D-Ala2]methionine enkephalinamide (DAMEA). The effect dissappeared at concentrations above and below this range. The inhibition approached 50% and was statistically significant (p<0.001). An increase in the time of incubation of the opioid with cells results in the shift of tile maximal effect to the lower concentrations of opioid (from about 10-13 to 5"10 -15 M) and decrease in the value of the effect. The antagonist of opioid receptors naloxone in 10-7 M abolishes the i~khibitory effect of 10-14 M DAMEA (10 rain incubation) on respiratory burst: the effect decreases from 40+/-7% to 6+/-2% (lrtean +/- SEM) in the presence of naloxone. Treatment with naloxone alone had no significant effect on respiratory burst. Aminoacids constituting DAMEA do not have any effect on tile respiratory burst when added in 10-14 M. These data indicate that hahibitory effect of DAMEA is mediated by specific opioid receptors.