P.4.a Anxiety disorders and anxiolytics – Anxiety disorders (clinical) Patients underwent an 8-week double-blind, flexible-dose (between 150 and 600 mg/d) treatment phase, including a 1-week titration period (50 mg/d to 150 mg/d). The primary efficacy assessment was change from baseline (last observation carried forward) in HAM-A total score. Analysis of covariance was performed with treatment and center in the model, and baseline HAM-A score as the covariate. Adjusted least-squares mean and 95% confidence intervals on the difference in HAM-D change scores were calculated. Results: The mean age of GAD onset in the study sample was 56 years, with a mean duration of 17 years. Seventyseven percent of patients were women, with a mean (± SD) age of 72±6 years. At baseline, the mean (± SE) HAM-A total score was similar on pregabalin (26.2±0.4) and placebo (26.7±0.4). On a repeated-measures mixed-effect model analysis, treatment with pregabalin was associated with significantly greater improvement in the HAM-A total score from week 2 (−9.8±0.6 vs −7.5±0.8; P = 0.0052) through week 8 (−14.4±0.6 vs −11.6±0.8; P = 0.0070). Pregabalin-treated patients also had a significant decrease from baseline in least-squares mean HAM-D score compared with those who received placebo (−5.48 vs −4.02, P = 0.041). The most common adverse events (AEs) among pregabalin-treated patients (compared with patients who received placebo) were dizziness (20.3% vs 11.5%), somnolence (13.0% vs 7.3%), headache (10.2% vs 8.3%), and nausea (9.0% vs 6.3%). Most AEs were mild-to-moderate and self-limiting. Nineteen pregabalin-treated patients (10.7%) and 9 of those who received placebo (9.4%) discontinued due to AEs. The most common reasons for discontinuation among pregabalin-treated patients were dizziness (4.5%), somnolence (1.1%), and vomiting (1.1%). The most common reason for discontinuation among patients who received placebo was nausea (3.1%). Conclusions: Pregabalin-treated patients achieved a significantly greater reduction from baseline in HAM-A total score than did patients who received placebo. Pregabalin was effective in reducing the symptoms of GAD in patients aged 65 years and older, and was safe and well tolerated in this population. References [1] Flint AJ, 1994, Epidemiology and comorbidity of anxiety disorders in the elderly, Am J Psychiatry, 151, 640–649. [2] Kessler RC, Berglund P, Demler O, Jin R, Merikangas KR, Walters EE, 2005, Lifetime prevalence and age-of-onset distributions of DSM-IV disorders in the National Comorbidity Survey Replication, Arch Gen Psychiatry, 62, 593–602.
P.4.a.021 Sleep in obsessive-compulsive disorder: a comparative study with “non-melancholic” depression A. Matos-Pires ° , F. Arriaga. Faculty of Medicine of Lisbon and Hospital de Santa Maria, Department of Psychiatry, Lisbon, Portugal Introduction: Numerous EEG sleep studies have identified a distinctive sleep profile in patients with severe forms of depression. However it remains unclear whether anxiety disorders, such a obsessive-compulsive disorder, are associated with distinctive EEG sleep profiles. In what regards subjective complaints, the information available is even scarcer. The nature of sleep and sleep-related symptoms in anxiety and mood disorders has not been fully investigated. Within this topic, our study purports to
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investigate the diagnostic significance of clinical and polysomnographic variables in obsessive compulsive disorder and “nonmelancholic” depression. Methods: The participants were outpatients selected according to DSM-IV (APA, 1994) criteria for “obsessive compulsive disorder” (OCD) (n = 14) and “major depressive disorder” without melancholic features (MDD) (n = 14). Both groups were comparable for socio-demographic variables, personality traits and spurious illness evolution attributes. Depressive comorbidity was excluded in OCD patients. The subjective quality of sleep was assessed using the Oswald scale. The insomnia items from the HDRS were also rated. The Norris scale was used to evaluate the subjective state upon waking. Sleep records were scored according to Rechtschaffen and Kales criteria (1968) by a trained electroencephalographer unaware of the diagnostic classification (OCD or MDD) of each subject. Either the chi2 test or the oneway analysis of variance (assuming a model II ANOVA) was used for statistical purposes in order to discriminate the two groups. Results: About subjective measures of sleep significant differences were found between the two groups of patients in “early” and “middle” insomnia (higher scores in MDD). Regarding sleep continuity variables, OCD patients showed a higher total sleep time (TTS) and a lower morning awake (MA). Sleep architecture measures displayed a lower percentage of wake, stage 1, stage 3 and REM and a higher stage 2%. However, REM sleep latency was comparable in the two groups. Both groups presented a reduced and fragmented sleep and a diminished percentage of slow wave sleep. Conclusions: With regard to the subjective characteristic of sleep and subjective state at waking both diagnostic groups present pervasive and intense complaints, more severe in the MDD group. OCD patients do not exhibit the typical REM sleep disturbances of “melancholic” depression, and the same holds true for “nonmelancholic‘’ depressive patients. Sleep continuity and sleep architecture seems to be disturbed in OCD patients. However, the findings don’t appear to be useful as diagnostic predictors. Along with other data, these sleep EEG data suggest the existence of a neurophysiological continuum encompassing OCD and “nonendogenous” depressions currently diagnosed as major depressive disorders. References [1] APA, 1994, Diagnosis and statistical manual of mental disorders, 4th ed., Washington DC, American Psychiatric Association. [2] Rechtschaffen A., Kales A., 1968, Manual of standardized terminology, techniques and scoring systems for sleep stages of human subjects, Washington DC, US Public Health Service, Government Printing Office.
P.4.a.022 Association study of limbic systemassociated membrane protein gene polymorphisms in panic disorder E. Maron1 ° , K. Koido2 , A. Must2 , A. Reimets2 , S. K¨oks2 , E. Vasar2 , V. Vasar1 , J. Shlik3 . 1 University of Tartu, Department of Psychiatry, Tartu, Estonia; 2 University of Tartu, Department of Physiology, Tartu, Estonia; 3 University of Ottawa, Department of Psychiatry, Ottawa, Canada The limbic system-associated membrane protein (LSAMP) is a 64−68 kDa glycoprotein expressed on the surface of somata and proximal dendrites of neurons in cortical and subcortical regions of the limbic system in the brain (Pimenta et al., 1998). The
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P.4.b Anxiety disorders and anxiolytics – Anxiety disorders (basic)
functional analysis indicates that LSAMP acts as a selective adhesion molecule, serving as a guidance cue for specific patterns of connectivity, which underlies the normal development of the limbic system (Pimenta et al., 1996). In animal studies there have been found that rats with high level of anxiety had 1.6fold higher expression of LSAMP gene compared to rats with low level of anxiety, indicating the possible role of LSAMP in the regulation of anxiety (Nelovkov et al., 2003). In the present case-control genetic association study we investigated whether panic disorder (PD) phenotype is related to four single nucleotide polymorphisms (SNP) of TPH2, (rs10934308 G/T, rs7632246 A/C, rs4831219 C/G, and rs1731607 C/T) The study sample consisted of 154 (125 females and 29 males) PD patients with or without affective comorbidity and 252 (183 females and 69 males) matched healthy control subjects. The tetra-primer ARMS PCR method was applied for genotyping selected SNPs, following association analysis with Haploview program. The allelic analyses demonstrated that at lest one of studied SNPs, rs7632246 A/C, positively associated with PD phenotype (c2 = 5.79, P = 0.016), suggesting its possible role in predisposition to PD. However further research on a functional role of LSAMP polymorphisms in PD is needed. References [1] Pimenta A.F., Fischer I., Levitt P., 1996, cDNA cloning and structural analysis of the human limbic-system-associated membrane protein (LAMP), Gene, 170, 189–195. [2] Pimenta A.F., Tsui L.C., Heng H.H., Levitt P., 1998, Assignment of the gene encoding the limbic system-associated membrane protein (LAMP) to mouse chromosome 16B5 and human chromosome 3q13.2-q21, Genomic, 49, 472–474. [3] Nelovkov A., Philips MA., Koks S., Vasar E., 2003, Rats with low exploratory activity in the elevated plus-maze have the increased expression of limbic system-associated membrane protein gene in the periaqueductal grey, Neurosci. Lett., 352, 179–182.
P.4.b Anxiety disorders (basic) P.4.b.001 Anxiolytic and reward-related properties of URB597, a novel FAAH inhibitor, in CD1 mice E. Ognibene1 ° , W. Adriani2 , G. Laviola2 . 1 Istituto Superiore di Sanit`a, Dept Cell Biol and Neuroscience, Rome, Italy; 2 Istituto Superiore di Sanit`a, Dept Cell Biology and Neuroscience, Rome, Italy URB597 is a potent and selective inhibitor of fatty acid amide hydrolase FAAH, the enzyme responsible for the degradation of the endogenous cannabinoid anandamide. The blockade of FAAH seems to be responsible for behavioural effects attributable to increased anandamide levels. The first aim of the present study was to compare the acute effect of URB597 and diazepam, used as the reference anxiolytic compound, on anxiety-like behaviour in the elevated plus-maze test. We also tested the motor/exploratory activity and the novelty response in the open field test. Our second aim was to investigate if the URB597 in mice may influence the reward related circuits, and for this purpose we compared the effect of URB597 and d-amphetamine, used as the reference addictive compound, on reward-related behaviour in the conditioned place preference test. URB597 seems to be not able to mimic the effect of delta9-THC in a two lever operant paradigm. Nevertheless, none of the above mentioned results has been reported on mice. In the elevated plus-maze, a lower anxiety level, measured as time spent in open arms and frequency of unprotected head-dipping, appeared in URB597 and diazepam
treated group, a dose-dependent significant difference was found [F (3, 74) = 4.209, p < 0.01]. In the open field test, drugs did not affect locomotor activity nor the ethological parameters scored in the test. On the other hand, the response to novelty, measured as time spent in contact with the novel object inserted in the central square of the arena, revealed a significant treatment effect [F (3, 36) = 3.696, p < 0.05]. In the conditioned place preference test the amphetamine group spent more the time in the paired chamber than in the unpaired compartment [F (3, 36) = 6.11, p < 0.05 vs vehicle group]. On the contrary, mice treated with all doses of URB597 did not show preference for the paired or even a tendency to prefer the unpaired room. No significant difference was found in the activity rate in each chamber and in the number of transition done between each chamber and the central area within-treatment group factor. The findings of the present study support anandamide involvement in modulation of anxietylike behaviour, and suggest that URB597 can be the prototype of a promising class of novel anxiolytic drugs, without affecting reward-related behaviour. References [1] Adriani W and Laviola G, 2003, Elevated level of impulsivity and reduced place conditioning with d-amphetamine: Two behavioral features of adolescence in mice, Behavoiral neuroscience, 117, 695–703. [2] File SE, 1996, Recent developments in anxiety, stress, and depression, Pharmacol Biochem Behav, 54, 1, 3−12. [3] Kathuria S, Gaetani S, Fegley D, Vali˜no F, Duranti A, Tontini A, Mor M, Tarzia G, La Rana G, Calignano A, Giustino A, Tattoli M, Palmery M, Cuomo V and Pomelli D, 2003, Modulation of anxiety through blockade of anandamide hydrolysis, Nature Medicine, 9, 76−81.
P.4.b.002 The central neuropeptide S system: expression, pharmacology and behavioural significance of neuropeptide S receptors S.K. Leonard ° , E. Kouranova, C. Bender, J.E. Malberg, L.E. Schechter, B. Luo, B. Platt, L. Potestio, C.E. Beyer, S. Rosenzweig-Lipson, R.H. Ring. Wyeth Research, Discovery Neuroscience, Princeton, New Jersey, USA The Neuropeptide S receptor (NPSR) is a recently de-orphaned G-protein coupled receptor (GPCR) implicated in the regulation of anxiety and arousal (Xu 2004). The endogenous ligand for NPSR, Neuropeptide S (NPS), is a 20 amino acid peptide with strong sequence conservation across mammalian species. To date, only a single isoform of NPSR has been identified in rodents. In contrast, eight isoforms have been reported in humans, each resulting from differential splicing of the hNPSR gene (Laitinen 2004). mRNA encoding the NPS precursor and NPSR have been localized to rodent brain circuits involved in arousal and in anxiety (Xu 2004), however the distribution of the hNPSR splice variants is unknown. In this study we determined the pattern of expression for mRNAs encoding six reported hNPSR variants (A, D, E and F; B; G) in both peripheral (n = 39) and central (n = 28) human tissues using quantitative RT-PCR (TaqMan) analysis. We report that all variants exhibit similar patterns of expression across peripheral tissues, with the highest levels of mRNA observed in retina and testis. In the central nervous system, moderate expression was observed in the hypothalamus, hippocampal formation, substantia nigra, and amygdala. Overall, the distribution of the human NPSR isoforms is similar to that reported previously for rat NPSR. We have investigated and compared the pharmacology of the mouse receptor (mNPSR) with that of select human NPSR isoforms (hNPSR A, hNPSR BLONG ). Each receptor was stably expressed