Now showing items 1-10 of 45
The effects of aging in normal men on bioavailable testosterone and luteinizing hormone secretion: response to clomiphene citrate
(Endocrine Society, 1987-12)
Serum testosterone (T) levels in men decline with age while serum LH levels, as measured by RIA, increase. To assess if the decline in serum T levels in healthy aging men is paralleled by an age-related decline in the bioavailable non-sex hormone-binding globulin (SHBG)-bound fraction of T and to ...
Abnormal patterns of pulsatile luteinizing hormone in women with luteal phase deficiency
Luteal phase deficiency is usually a problem of inadequate progesterone production associated with inadequate ovarian follicular development. The hypothesis that luteal phase deficiency results from an abnormal secretion pattern of luteinizing hormone (LH) was tested in these women. To this end, ...
Decreased serum inhibin levels in normal elderly men: evidence for a decline in Sertoli cell function with aging
(Endocrine Society, 1988-09)
Compared to young men, normal elderly men have decreased sperm production despite elevated serum gonadotropin levels. To determine whether the seminiferous tubule defect in elderly men includes decreased Sertoli cell function, we measured serum immunoreactive inhibin concentrations in young and ...
The importance of luteinizing hormone in the control of inhibin and progesterone secretion by the human corpus luteum
(Endocrine Society, 1989-06)
Serum inhibin levels rise markedly during the luteal phase of the human menstrual cycle and are closely correlated with serum progesterone (P) levels, suggesting that the corpus luteum (CL) secretes inhibin. While FSH is the major regulator of inhibin secretion by the granulosa cells, the control ...
Luteal phase deficiency: characterization of reproductive hormones over the menstrual cycle
(Endocrine Society, 1989-10)
The recurrent deficiency of progesterone (P) secretion by the corpus luteum has been associated with infertility and habitual abortion and given the clinical diagnosis of luteal phase deficiency (LPD). There is evidence that both follicular and luteal phase abnormalities can result in LPD cycles. ...
Diminished luteinizing hormone pulse frequency and amplitude with aging in the male rat
(Endocrine Society, 1983-03)
Aging in the male rat is associated with a reduction in circulating testosterone levels. One possible cause of this decline is an age-related alteration of central nervous system-mediated LH secretion. To examine the effects of age on the hypothalamo-hypophyseal system, in the absence of gonadal ...
Stimulation of Sertoli cell inhibin secretion by the testicular paracrine factor PModS
The testicular paracrine factor PModS is produced by peritubular myoid cells under androgen control and modulates Sertoli cell function and differentiation. The observation that luteinizing hormone (LH) stimulates inhibin production in vivo, but has no effect on isolated Sertoli cells in vitro, ...
Nocturnal slowing of pulsatile luteinizing hormone secretion in women during the follicular phase of the menstrual cycle
(Endocrine Society, 1985-07)
The gonadotropin secretion pattern in normal reproductive age women (n = 5) was evaluated for the presence of a circadian rhythm. The women volunteered for a series of 24-h admissions in different phases of their menstrual cycles (early follicular, late follicular, and midluteal). Plasma LH and FSH ...
Endocrine correlates of sexual development in the male monkey, Macaca fascicularis
(Endocrine Society, 1981-09)
No abstract or description.
Follicle-stimulating hormone is required for quantitatively normal inhibin secretion in men
(Endocrine Society, 1988-12)
Inhibin is a glycoprotein hormone produced by the testis and ovary which is postulated to be an important regulator of pituitary FSH secretion. Animal data indicate that inhibin is produced by the Sertoli cells of the testis under the influence of FSH. To determine the role of FSH withdrawal and ...