Premature ovarian failure: a search for circulating factors against gonadotropin receptors

Nine patients with premature ovarian failure, one of whom had the associated autoimmune disorders rheumatoid arthritis, Hashimoto's thyroiditis, and vitiligo, were examined for the presence of a serum factor which would interfere with gonadotropin-receptor interaction in a bovine testicular membrane system. Sera from nine premenopausal and nine postmenopausal women served as control subjects. Mean displacement of radiolabeled follicle-stimulating hormone (FSH) and luteinizing hormone (LH) from receptors was not significantly different among the three groups. However, the greatest interference with FSH-receptor interaction was detected in the patient with both premature ovarian failure and autoimmune diseases. No differences in mean serum levels of IgG, IgM, and IgA were found among the premature ovarian failure and the two control groups, nor were immunoglobulin levels different in the otherwise unique subject (premature ovarian failure and autoimmunity). Our study suggests that anti-gonadotropin receptor factors are unlikely to be involved in the majority of patients with premature ovarian failure. However, an anti-FSH receptor factor, possibly an antibody, may be present in some patients, particularly those who have concomitant autoimmune disorders.

Structure-activity relationships of estrogens. Effects of 14-dehydrogenation and axial methyl groups at C-7, C-9 and C-11

Thirty compounds were evaluated in the rat for uterotropic effects, inhibition of gonadotropin release, and competitive displacement of (3H) estradiol-17 beta from uterine cytosolic preparations. 7 alpha-Methylestradiol-17 beta was 150% as active as estradiol-17 beta as an uterotropic agent. Estradiol-17 beta was the most active inhibitor of gonadotropin release. 11 beta-Methylestradiol-17 beta had 124% of the activity of estradiol-17 beta in displacing (3H) estradiol-17 beta from the "estrogen receptor." The 9 alpha-methyl group considerably decreased the potency of estrogens in any of the three assays. The 14-dehydro modification was advantageous only in the estradiol-17 beta 3-methyl ether series. Uterotropic activities and inhibition of gonadotropin release did not parallel. The best compound for inhibiting gonadotropin release, as compared to uterotropic activity, was estrone. The "estrogen receptor" assay data correlated fairly well with uterotropic assay data, but only for compounds having free 3-hydroxyl groups; even so, some exceptions were noted.

Danazol: endocrine consequences in healthy women

We studied the effects of danazol on pituitary and gonadal function in seven normal women who volunteered to take danazol, 400 mg twice daily, for 2 months. We measured circulating levels of sex steroids, gonadotropins, and prolactin on alternate days throughout a control menstrual cycle and during treatment. Danazol inhibited ovulation in all subjects. The amenorrheic state induced by danazol was characterized by normal basal levels of gonadotropins, prolactin, and estrogen. Serum androgen levels were significantly increased as was the urinary excretion of 17-ketosteroids. The LH and FSH responses to gonadotropin-releasing hormone were enhanced during treatment, and there was a normal LH rise following administration of estradiol valerate, indicative of intact positive feedback. These observations fail to support the contention that danazol suppresses pituitary gonadotropin secretion or directly inhibits steroidogenesis. The results suggest that danazol may have a primary site of action at the ovary by suppressing the normal, orderly process of follicular maturation.

Utility of assay of alpha subunit of human chorionic gonadotropin in management of gestational, trophoblastic malignancies

All patients who were treated with chemotherapy for malignant gestational trophoblastic neoplasms at the Southeastern Regional Trophoblastic Disease Center and who experienced remission during the period January 1, 1978, through December 31, 1979, were studied in an attempt to determine if the application of an assay for the alpha subunit of human chorionic gonadotropin (hCG-alpha) could predict those patients who would have recurrences. For each patient, the first three weekly serum samples with undetectable HCG by the hCG beta-subunit radioimmunoassay as well as the two preceding samples with detectable hCG were assayed in a homologous hCG-alpha assay. Results reaffirm previous data that the latter assay is useful only in patients receiving oral contraceptives for suppression of pituitary gonadotropin secretion. No patient who has remained in remission had a mean level of hCG-alpha in the three hCG-negative samples greater than 1 ng/ml. Of those patients who had recurrences of trophoblastic disease, two of three had hCG-alpha levels greater than 1.5 ng/ml. Although these data are preliminary, they suggest that the routine measurement of hCG-alpha in patients successfully treated for trophoblastic disease may aid in identification of a group of patients who require additional or more intensive follow-up and/or additional chemotherapy to prevent later recurrences.

Review: The mechanism of action of danazol, a novel steroid derivative

Danazol is being increasingly used for the treatment of a wide range of disorders, many of which appear to bear little relation to the condition for which the drug was originally marketed--endometriosis. It has been claimed that this drug acts by means of its antigonadotrophic effects on the pituitary; however, a review of the literature reveals that its efficacy in suppressing normal endometrial growth and in causing atrophy of deposits of endometrium cannot be explained solely on this basis. Recent information indicates that, besides acting at the pituitary level, a major mechanism of action may be by a direct inhibitory effect on target tissue. It is sugggested that such a mechanism would more readily account for the diverse effects of this drug in the treatment of many disorders, all of which appear to be associated with an imbalanced sensitivity of target organs to steroid hormones. A greater understanding of its mechanism of action could lead to an even wider application of this novel drug.

Inhibition of testosterone-induced prostate growth in the rat by melatonin-free pineal extract

Administration of the melatonin-free pineal extract to rats concomitantly receiving testosterone propionate caused partial inhibition of the ventral prostate growth induced by testosterone. Administration of the pineal extract to rats likewise caused a statistically significant decrease in the ventral prostate weight under basal conditions. The mechanism of action is discussed.

Blood flow in the reproductive tract of the domestic hen following treatment with a pituitary gonadotropic inhibitor

The effect of pituitary gonadotropic inhibitor--methallibure on the weight and blood flow through reproductive tract was studied in immature hens. It was found that methallibure lowers the weight of the reproductive tract and simultaneously inhibits (about 2--3 times) the blood flow through the ovary and oviductal segments. However, the action of methallibure is of short duration and it is limited to the time of its administration only.

Pituitary gonadotropin inhibition by a highly active analog of luteinizing hormone-releasing hormone

Chronic treatment with highly active analogs of luteinizing hormone (LH)-releasing hormone (LH-RH) induces "paradoxical" antifertility effects. Intact male rats, a reduction in testosterone production is observed after the administration of [D-Ser(But)6]-LH-RH(1-9)ethylamide (burserelin, Hoe 766), 50 ng/day subcutaneously for 4 weeks. In castrated male rats treated with the same dose of analog, plasma LH levels were reduced from days 14 to 28 and plasma follicle-stimulating hormone (FSH) levels were reduced from days 21 to 28 of treatment. Pituitary LH and FSH concentrations were also decreased. The plasma prolactin level was reduced at 14 days of treatment. The hypothalamic LH-RH content remained unchanged and the adrenal corticosterone content was lowered. These findings indicate a direct inhibitory effect of the analog on gonadotropin secretion in the absence of the gonads, and may explain some paradoxical antifertility effects observed with high doses of LH-RH analogs which exceed the physiologic dose range.

Isolation, synthesis, and biological activity of five metabolites of danazol

Metabolites of danazol (17 alpha-pregna-2,4-dien-20-yno[2,3-d]isoxazol-17-ol), an orally effective pituitary gonadotropin inhibitory agent devoid of estrogenic and progestational activites, were isolated from urine of a female subject who had taken danzol orally at a dose of 800 mg/day for 7 days, The metabolites isolated were 17-hydroxy-17alpha-pregn-4-en-20-yn-3-one (11), 17-hydroxy-2alpha-(hydroxymethyl)-17alpha-pregn-4-3n-20-yn-3-one (5), 17-hydroxy-2-(hydroxymethyl)-17alpha-pregna-1,4-dien-20-yn-3-one(7), 6beta,17-dihydroxy-2alpha-(hydroxymethyl)-17alphapregn-4-en-20-yn-3-one(8), and 6beta, 17-dihydroxy-2(hydroxymethyl)-17alphapregna-1,4-dien-20yn-3-one(10). None of these metabolites exhibited pituitary inhibiting activity comparable to danazol.

[Antigonadotropic actions of prolactin. Study of 10 cases of women with hyperprolactinemia]

In order to determine the pituitary or ovarian site of the anti-gonadotrophic action of prolactin (PRL), ten women with hyperprolactinaemia were studied in the following way: 1) Repeated estimations of PRL, gonadotrophins (LH and FSH), plasma estradiol and progesterone during six weeks of treatment with bromocriptine. 2) Verification of the effects of estradiol benzoate on LH and FSH levels before and after normalisation of prolactin. 3) Exploration of the ovarian response to the administration of human menopausal gonadotrophin. Without it being possible to exclude any direct effect of prolactin on the ovary, it may be affirmed that the hormone decreases the sensitivity of the gonadotrophic cells to the positive feedback mechanism exerted by plasma estradiol.

Quantitation of ultrastructural changes in the mouse pineal in response to continuous illumination

Adult male mice were exposed to either alternating illumination or constant illumination for 70 days. Light and dark pinealocytes were compared as to distribution within the gland and ultrastructure. Quantitative studies with the electron microscope revealed a significant reduction in pinealocyte size and Golgi complex size in constant light treatment, as well as a marked but nonsignificant reduction in the concentration of lipid droplets and irregular vacuoles. Under constant light treatment the cross-sectional area of pinealocyte pericapillary terminals and the number of granulated vesicles per terminal decreased significantly. A greater number of mitochondria appeared swollen, with rarified matrix and reduced numbers of cristae, with constant light treatment. These results provide ultrastructural correlation with the known reduction of pineal weight, protein synthesis and antigonadotrophic activity that is seen with constant light treatment. The marked decrease in concentration of pinealocyte granulated vesicles in constant light treatment gives morphological support to the theory that these vesicles contain antigonadotrophic secretory material.

Effect of clomiphene on basal and LRH-induced gonadotropin secretion in postmenopausal women

LRH tests were performed in 11 postmenopausal women before and after the administration of 200 mg of clomiphene citrate daily by mouth for 7 consecutive days. The basal levels and the maximum increments of serum LH (deltaLH) and the area under the response curve from basal level (deltaarea) after LRH administration, significantly (P less than 0.005) decreased after consecutive administration of this compound. Serum FSH levels were significantly (P less than 0.025) decreased but deltaFSH and deltaarea in LRH test were statistically unchanged. These results suggest that clomiphene citrate in postmenopausal women inhibits the pituitary gonadotropin response to exogenous LRH by its estrogenic effects.

Influence of neonatal castration or neonatal anti-gonadotropin treatment on fertility, phallus development, and male sexual behavior in the mouse

Male mice were castrated on the day of birth or were treated with anti-gonadotropin serum (AGS) successively on days 1, 3, and 5 of age. When the adult AGS-treated males were compared with normal rabbit serum (NRS)-treated males with respect to fertility, male sexual behavior, gonadotropin release, body size, and penis size it was found that: (1) fertility of AGS-treated males did not differ from that of NRS-treated males; (2) AGS-treated males showed a significant reduction in penis size, compared with NRS-treated males; (3) both groups showed high levels of male sexual behavior; (4) neither group showed the capacity to support ovulation in ovarian grafts from immature mice. It was also observed that the fertility of female mice treated with AGS on days 1, 3, and 5 of age did not differ from that of control females treated with comparable doses of NRS. Male mice castrated at birth showed a significant reduction in male sexual behavior and penis size compared with males first sham-operated at birth then castrated at 25 days of age. Thus, males castrated at birth were similar to males receiving AGS in infancy, except for sex behavior. The results suggest that the neonatal pituitary in the mouse may not have an important role in the process of sexual differentiation. Previous data for the male rat were compared with those for the mouse.