A central event in mammalian reproduction is the LH surge that induces ovulation and corpus luteum formation. Typically, the LH surge is initiated in ovariectomized rats by sequential treatment with estrogen and progesterone (PROG). The traditional explanation for this paradigm is that estrogen induces PROG receptors (PR) that are activated by exogenous PROG. Recent evidence suggests that where...

Carcinoma in the dorsal prostate of Nb rats was produced by prolonged treatment with androgen or androgen plus estrogen. The most effective combination was androgen followed by estrogen, resulting in an incidence of 50% in 10 rats. In such a case, the rats did not show evidence of androgenization. Transplants were usually not sensitive to hormones, but an estrogen-dependent tumor (Nb-2Pr-E) was...

Clinical trials and animal studies have revealed that loss of circulating estrogen induces rapid changes in whole body metabolism, fat distribution, and insulin action. The metabolic effects of estrogen are mediated primarily by its receptor, estrogen receptor-α; however, the detailed understanding of its mechanisms is incomplete. Recent investigations suggest that estrogen receptor-α elicits t...

The steroid hormone estrogen regulates many functionally unrelated processes in numerous tissues. Although it is traditionally thought to control transcriptional activation through the classical nuclear estrogen receptors, it also initiates many rapid nongenomic signaling events. We found that of all G protein-coupled receptors characterized to date, GPR30 is uniquely localized to the endoplasm...

Objective: To see how dose of Silymarin aqueous extracts affected prolactin hormone gene expression in pituitary glands and Androgen serum samples female experimental rats throughout nursing. Methods: 24 adult healthy, Two sets pregnant were created (12 each group) treated as follows for ten days postnatal. G 1 intubated orally distal water serving control while, 2 (200 mg\kg\day). Results: The...

CONTEXT Whether menopausal hormone replacement therapy using a combined estrogen-progestin regimen increases risk of breast cancer beyond that associated with estrogen alone is unknown. OBJECTIVE To determine whether increases in risk associated with the estrogen-progestin regimen are greater than those associated with estrogen alone. DESIGN Cohort study of follow-up data for 1980-1995 from...

PURPOSE Intratumoral metabolism and synthesis of estrogens are considered to play important roles in the pathogenesis and/or development of human endometrial carcinoma. Steroid sulfatase hydrolyzes biologically inactive estrogen sulfates to active estrogens, whereas estrogen sulfotransferase sulfonates estrogens to estrogen sulfates. However, the status of steroid sulfatase and/or estrogen sulf...

CONTEXT Clinical trial evidence indicates that estrogen therapy with or without progestins increases venous thrombotic risk. The findings from these trials, which used oral conjugated equine estrogens, may not be generalizable to other estrogen compounds. OBJECTIVE To compare risk of venous thrombosis among esterified estrogen users, conjugated equine estrogen users, and nonusers. DESIGN, S...