Vol 11, No 1-2 (2011)

Smagin DA, Galyamina AG, Bondar NP, Kudryavtseva NN. [ Effects of clomipramine on mixed anxiety/depression state produced by chronic social defeat stress in male mice]. Psychopharmacol Biol Narcol. 2011; 11(1-2). Epub 14 June 2011. Russian. BACKGROUND. Chronic social defeat stress in daily agonistic interactions leads to development of mixed anxiety/depression state in male mice. Paper aimed to study effects of clomipramine on psychoemotional state in these animals with point on level of anxiety and depression. METHODS. Mixed anxiety/depression state was produced by chronic social defeat stress during 20 days in male mice. Clomipramine (20, 40 mg/kg, i/p, SIGMA) and saline were chronically injected to chronically defeated mice during 2 weeks without agonistic interactions. After resting period the male mice were investigated in the partition, plus-maze and Porsolt' tests. RESULTS. Clomipramine in dose 40 mg/kg decreased communicativeness in the partition test, produced anxiogenic effects and decreased exploratory activity in the plus-maze test and had antidepressive effect in the Porsolt' test. Clomipramine in dose 20 mg/kg had weak antidepressant effect and did not affect enhanced level of anxiety. CONCLUSION. Clomipramine produces anxiogenic and antidepressant effects on mixed anxiety/depression state in male mice. It is supposed, that clomipramine, at least in dose of 40 mg/kg, may independently influence on anxiety and depression states. Date submitted: March 22, 2011; Accepted: June 14, 2011. Citation: Psychopharmacol Biol Narcol. 2011;11(1-2):2666-2676

Bondar NP, Smagin DA, Kudryavtseva NN. [Effects of single and chronic naltrexone treatment on agonistic behavior of male mice with repeated experience of aggression]. Psychopharmacol Biol Narcol. 2011; 11(1-2). Epub 14 Oktober 2011. Russian. BACKGROUND. Experimental studies have shown that the effect of clinical drugs (diazepam, buspirone, haloperidol, etc.) on aggressiveness of male mice with repeated experience of aggression accompanied by victories depended on the duration of aggression experience. The aim of this study was to examine in detail in experienced winners antiaggressive effects of blocker of opioid receptors naltrexone, which effectively reduces the aggression in males without a consecutive experience of aggression. METHODS. Effects of naltrexone (single injection, 1 and 2 mg/kg, s.c.) were examined in male mice after 3, 10 and 20 days of intermale interactions, as well as in males with 20-days aggressive experience after the cessation of agonistic interactions (deprivation). In addition, naltrexone (2 mg/kg, s.c) was administered chronically from the 7th day for 2 weeks on ongoing agonistic interactions. 20-days experienced winners were also injected chronically during 2 weeks deprivation. RESULTS. Single injection of naltrexone effectively reduced the aggression in male mice with 3 and 10 days aggressive experience, but had no effect on male mice with 20 days experience. Naltrexone produced antiaggressive effect in males after period of deprivation. Chronic treatment with naltrexone on the background of aggressive interactions had no significant protective effect on most parameters, evaluating agonistic behavior, increasing aggressive motivation and total time of hostile behavior toward a partner. Chronic naltrexone treatment during deprivation did not prevent post-deprivation increase of aggression and even somewhat increased indirect aggression (diggings of partner's sawdust). CONCLUSION. Single treatment by naltrexone decreases aggression in male mice with small experience of aggression and is ineffective in male mice with prolonged aggressive experience. Period of deprivation restors sensitivity to antiaggressive effects of naltrexone. Chronic blockade of opioid receptors that mediates positive reinforcement has no significant effect on aggression in experienced winners. Date submitted: July 24, 2011; Accepted: Oktober 13, 2011. Citation: Psychopharmacol Biol Narcol. 2011;11 (1-2):2688-2700