Involvement of the ventromedial and anterior hypothalamic nuclei in the hormonal induction of receptivity in the female rat

Bilateral lesions of the ventromedial hypothalamic area virtually eliminated the estrogen-induced display of sexual receptiveness in the female rat. Such lesions usually diminished sexual responsiveness to combined estrogen-progesterone stimulation, although not all lesions were equally effective in this regard. Damage to the anterior hypothalamic area was without apparent effect on the hormonally-induced display of receptivity, suggesting that previous observations to this effect are probably related to incidental damage to the ventromedial hypothalamic area incurred during placement of the lesions. This study complements other work indicating that the ventromedial hypothalamic area is relatively rich in estradiol concentrating cells and that estrogen implants to this area induce sexual receptivity in spayed female rats. Together, these studies affirm that the ventromedial hypothalamic area plays a critical role in the hormonal induction of receptivity in female rats.