ANTISEXUAL AND ANXIOGENIC BEHAVIORAL CONSEQUENCES OF CORTICOTROPIN-RELEASING FACTOR OVEREXPRESSION ARE CENTRALLY MEDIATED

Corticotropin-releasing factor (CRF) acts as a neurotransmitter in bra in to promote behavioral responses such as flight and immobility, whic h have adaptive value in the context of exposure to environmental stre ssors. CRF also suppresses behavioral repertoires such as mating, whic h are incompatible with such threat-related coping responses. In this study, we employed transgenic (Tg) mice which overexpress CRF in brain and exhibit a constitutive and persistent phenotype of emotionality i n order to determine the consequences of long-term CRF excess on indic es of reproductive success, male sexual performance and female sexual receptivity. Sexual performance of CRF Tg males was relatively intact, whereas female receptivity was masked in CRF Tg mice by active reject ion of sexually experienced male counterparts. This impairment in soci al interaction was only partially normalized by the serotonin antagoni st, methysergide, which enhanced olfactory exploration of the still no n-receptive CRF Tg females. Moreover, the anxiogenic-like character of CRF Tg mice is likely to be centrally mediated, since attenuation of hypercorticosteronemia by adrenalectomy did not alter either impaired sexual receptivity or fear-like behavior in an animal model of anxiety . Thus, overexpression of CRF in the brain results in a variety of adv erse consequences including diminished social interactions. (C) 1997 E lsevier Science Ltd.