The influence of estrogen administration on the subcellular receptors distribution and its biological effect in the rat anterior pituitary gland.
We studied the effects of estrogen administration in the anterior pituitary gland (APG) of male rats. The subcellular distribution of estradiol receptors, and some biological responses, such as prolactin secretion and progestine receptors were examined. In the presence of circulating estrogens, the binding of [3H]-estradiol decreased in the cytosol and increased in nuclei. The total binding augmented significantly (P less than 0.05). These changes were dose and time dependent. So, in long chronic treatment, the changes in subcellular receptor distribution were greater, in accordance with higher serum estrogen level. Serum prolactin concentration and progestin receptor in the APG increased continuously as a function of time of the estrogen treatment. They were related to the presence of nuclear estradiol receptors, which remained elevated throughout the entire experimental period.
D000818:Animals; D002451:Cell Compartmentation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004958:Estradiol / Q000494:pharmacology*; D008297:Male; D010903:Pituitary Gland, Anterior / Q000187:drug effects* / Q000378:metabolism; D011388:Prolactin / Q000378:metabolism; D051381:Rats; D011959:Receptors, Estradiol; D011960:Receptors, Estrogen / Q000187:drug effects* / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism
D011959:Receptors, Estradiol; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; D004958:Estradiol; D011388:Prolactin