Journal ArticleDOI
Effects of Estrogen and Progesterone on Serum and Pituitary Prolactin Levels in Ovariectomized Rats
C. L. Chen,Joseph Meites +1 more
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It is indicated that low doses of estrogen are more effective than high doses for increasing AP and serum prolactin levels, and no evidence that large doses of estroge...Abstract:
Serum and anterior pituitary (AP) prolactin levels from mature ovariectomized rats were assayed after injection with daily doses of 0.1–500 ng estradiol benzoate (EB) or 0.5–10 mg progesterone for 6 days. Doses of 0.1, 1 or 5 μg EB increased serum prolactin concentration 2-, 3- and 10-fold, respectively, over ovariectomized controls, and doses of 10–500 μg EB evoked smaller increases in serum and AP prolactin levels. AP prolactin concentration and content were increased 3- to 4-fold. Doses of 0.5, 1 or 4 mg progesterone partially inhibited the increase in serum prolactin levels evoked by 1 μg EB, but only the inhibition by 4 mg progesterone was significant. A daily dose of 4 mg progesterone injected alone appeared to have no effect on serum and AP prolactin levels, but a 10 mg dose significantly increased prolactin secretion. These results indicate that low doses of estrogen are more effective than high doses for increasing AP and serum prolactin levels, and provide no evidence that large doses of estroge...read more
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Journal ArticleDOI
Prolactin: Structure, Function, and Regulation of Secretion
TL;DR: The purpose of this review is to provide a comprehensive survey of the current understanding of prolactin's function and its regulation and to expose some of the controversies still existing.
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Prolactin and Murine Mammary Tumorigenesis: A Review
TL;DR: If prolactin can be shown to influence human breast epithelium in a manner similar to its effect on rodent mammary tissue, then prophylactic and/of chemotherapeutic control of human breast tumorigenesis may be feasible by appropriate drug-mediated Prolactin suppression.
Journal ArticleDOI
Gonadal effects on food intake and adiposity: a metabolic hypothesis.
George N. Wade,Janet M. Gray +1 more
TL;DR: It is suggested that during naturally-occurring reproductive states gonadal steroids interact with other hormones to partition available triglycerides among tissues which oxidize, excrete or store long-chain fatty acids, contributing to the changes in food intake.
Journal ArticleDOI
Chronological Changes in Sex Steroid, Gonadotropin and Prolactin Secretion in Aging Female Rats Displaying Different Reproductive States
TL;DR: The results suggest that continuous exposure to medium levels of estrogens, particularly in the presence of sustained low progesterone secretion, may alter pituitary secretion of prolactin in aging rats.
Journal ArticleDOI
Potent antidopaminergic activity of estradiol at the pituitary level on prolactin release
TL;DR: Prior incubation of rat anterior pituitary cells with 17beta-estradiol led to an almost complete reversal of the inhibitory effect of two dopamine agonists, dihydroergocornine and RU 24213, on both basal prolactin release and thyrotropin releasing hormone-induced prolactins.