Effects of mianserin and ketanserin on lordosis behavior after systemic treatment or infusion into the ventromedial nucleus of the hypothalamus.

The effects of the 5-HT2A/2C antagonists, mianserin and ketanserin, were investigated in proestrous rats and in ovariectomized rats hormonally primed with estradiol benzoate and progesterone. Drugs were administered systemically or by infusion into the vicinity of the ventromedial nucleus of the hypothalamus (VMN). By both routes of administration, inhibition of lordosis behavior was seen following treatment with the 5-HT2A/2C antagonists, but the magnitude of the decline was smaller in proestrous than in hormone-primed, ovariectomized rats. The results of these studies are discussed in terms of the dual role of serotonin in the control of female sexual behavior.