Estradiol modulation of alpha 2-noradrenergic receptors in guinea pig brain assessed by tritium-sensitive film autoradiography.

In this experiment, we examined the influence of estradiol on alpha 2-noradrenergic receptor binding in the female guinea pig brain with tritium-sensitive film autoradiography. Treatment of ovariectomized guinea pigs with estradiol increased alpha 2-receptor binding in regions of the preoptic area and decreased binding in the ventromedial nucleus of the hypothalamus. There was no effect of estradiol on alpha 2-receptor concentrations in other estradiol concentrating regions or in brain areas which do not concentrate estradiol.