Endocrine activity of the postmenopausal ovary: the effects of pituitary down-regulation and oophorectomy.

Abstract

The endocrine activity of the postmenopausal ovary and the effect of pituitary down-regulation were studied in a group of 35 postmenopausal women. All women underwent oophorectomy with or without hysterectomy. Fifteen women received a single dose of a depot GnRH agonist (GnRHa) 2 weeks before operation, whereas 20 women formed the control group. Peripheral venous levels of LH, FSH, estrone, 17 beta-estradiol, testosterone (T), androstenedione (A), sex hormone-binding globulin, and dehydroepiandrosterone sulfate were measured 2 weeks before, during, and 6 weeks after surgery. Ovarian venous blood was sampled during surgery. In the GnRHa and control groups, ovarian venous levels of A and T were significantly higher, and those of dehydroepiandrosterone sulfate and sex hormone-binding globulin significantly lower, compared to the peripheral levels. A significant decrease in T was found in the peripheral and ovarian vein samples during pituitary down-regulation with GnRHa. Six weeks after operation, peripheral T levels were significantly lower than those during surgery in the group that was down-regulated at the time of oophorectomy. We conclude that the postmenopausal ovary produces significant amounts of A and T, although only T contributes significantly to its peripheral serum levels. T production by the postmenopausal ovary is in part stimulated by the high levels of circulating gonadotropins, although pituitary down-regulation does not completely abolish androgenic activity.

Increased insulin-like growth factor-1 after oophorectomy in postmenopausal women

“…We have previously substantiated the hormonally active status of the postmenopausal ovary (25), confirming prior reports of other groups (26)(27)(28)(29)(30)(31)(32)(33). Using an improved method of blood collection for the ovarian venous effluent in addition to contemporary assay methods, statistically significant gradients between ovarian venous and peripheral concentrations of E 2 , E 1 , T, and A were demonstrated, confirming continued hormone production by the postmenopausal ovary.…”

“…Having previously demonstrated, along with others, that the postmenopausal ovary remains hormonally active (25)(26)(27)(28)(29)(30)(31)(32)(33), we hypothesized that oophorectomy would result in decreased circulating levels of steroid hormones, thereby modulating postoperative levels of IGF-1 and IGF-2, possibly leading to an altered risk of CRC in postmenopausal women.…”

Surgical Menopause

“…88 The removal of the premenopausal ovary and the sudden and significant reductions in testosterone and androstenedione are thought to have a negative impact on sexual desire. During subsequent years, women with surgical menopause continue to have lower levels of testosterone than those with intact ovaries, [21][22][23][24][25][26]89 and continued impact on sexual function is also suspect.…”

Répercussions somatiques et psychologiques des modifications hormonales liées aux traitements adjuvants des cancers du sein de la femme jeune

“…Avec les analogues de la LHRH, la diminution des taux circulants des androgènes ovariens n'est pas aussi importante qu'après ovariectomie bilatérale (Sluijmer, 1995).…”