EFFECTS OF PINDOBIND 5-HYDROXYTRYPTAMINE(1A) (5-HT(1A), A NOVEL AND POTENT 5-HT(1A) ANTAGONIST, ON SOCIAL AND AGONISTIC BEHAVIOR IN MALE ALBINO MICE

In view of inconsistent results reported for 5-hydroxytryptamine1A (5-HT1A) receptor involvement in murine social conflict, this study examined the effects of N1-(bromoacetyl)-N8-[3-(4-indolyloxy)-2-hydroxypropyl]-(Z)-1,8-diamino-p-menthane (pindobind) 5-HT1A, a novel 5-HT1A antagonist, on agonistic and social behaviour in mice. Employing a resident-intruder paradigm, administration of pindobind 5-HT1A (0.5-10 mg/kg) to resident animals produced a reduction in offensive sideways and chasing behaviour. Defensive postures were unchanged except for evasion, which was reduced. Within social behaviour, nonspecific social behaviour and following behaviour were reduced while stretch/attend behaviour was enhanced. Nonsocial behavioural changes included an increase in resident cage exploration and rearing. Intruder data indicated no significant change in offensive behaviours, an attenuation of defensive sideways posturing and evasion, decreases in attend behaviour, and increases in cage exploration, rearing, and digging. Results are discussed in relation to the effects of 5-HT1A receptor (ant)agonism on murine offensive behaviour.