STUDIES ON MATING BEHAVIOUR IN THE ANDROGEN-STERILIZED FEMALE RAT IN RELATION TO THE HYPOTHALAMIC REGULATION OF SEXUAL BEHAVIOUR

Abstract

SUMMARY In the present investigation the mating behaviour of the androgensterilized rat has been studied. It was observed that rats sterilized by prepubertal administration of 1·25 mg. of testosterone propionate were sexually unreceptive to the male. Progesterone, when given as either spaced or daily injections, did not restore mating behaviour. Furthermore, although mating behaviour could be restored in normal ovariectomized rats by combinations of oestrogen and progesterone, identical treatment of spayed sterile rats was ineffective. Rats pretreated with 10 μg. of testosterone propionate at 5 days of age were found to be sexually receptive to the male even though they exhibited the same anovulatory persistentoestrous syndrome as did rats which received the higher dose. One rat accepted the male for nine consecutive days whilst others exhibited more bizarre patterns of sexual receptivity. It is suggested from these and other studies that a ' mating centre' exists in the hypothalamus of the rat and that it is located in the anterior hypothalamus.