In vivo estrogen uptake by individual cell types of the rat anterior pituitary after short-term castration-adrenalectomy.

In vivo estrogen uptake was measured in five anterior pituitary cell types of the rat by a quantitative autoradiographic-immunocytochemical technique. In male and female rats that had been castrated and adrenalectomized for one day all five cell types showed nuclear concentration of label one hour after injection of 3H-estradiol. The order of labeling intensity was lactotropes > somatotropes > gonadotropes > corticotropes > thyrotropes. No significant overall sex difference in estrogen uptake was apparent although male pituitaries tended to take up slightly more. Physiological correlates to these data are discussed.