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At least 91 records · Page 5Linked to original sources
PubMed1977

Steroid sex hormones and prolactin in postmenopausal women with generalized mammary carcinoma during prolonged dexamethasone treatment.

The endocrine response to prolonged dexamethasone treatment was investigated in six postmenopausal women with generalized mammary carcinoma. Plasma cortisol levels decreased rapidly and became undetectable whereas significant concentrations of plasma dehydroepiandrosterone and androstenedione persisted throughout the study, even in two ovariectomized patients, indicating a certain degree of autonomy or a greater resistance of adrenal 'androgens' to the inhibition of ACTH secretion. Except in the ovariectomized patients, plasma testosterone did not fall significantly whereas the plasma oestrogens tended progressively towards undetectable concentrations. A similar response was found in six normal postmenopausal women although the disappearance of their oestrogens was relatively rapid. This indicates that much of the testosterone present after the menopause could still be produced by the ovaries whereas the ovarian production of oestrogens becomes negligible. The delayed disappearance of oestrogens in the patients with mammary carcinoma indicates that the persisting adrenal 'androgens' remained efficient precursors of oestrogen synthesis within the peripheral tissues and presumably within the mammary tumour itself. Plasma dihydrotestosterone behaved like the plasma oestrogens. Despite the fall in plasma oestrogens, plasma gonadotrophins did not increase further but plasma prolactin rose progressively. The persistance of steroid sex hormones and the rise of plasma prolactin might explain the poor response to dexamethasone treatment in mammary carcinoma.

Aged↗
PubMed1992

Hormone levels and anogenital swelling of female chimpanzees as a function of estrogen dosage in a combined oral contraceptive.

A combined oral contraceptive consisting of ethinyl estradiol (EE2) in three dosages (50, 100, and 400 micrograms) and norethindrone (0.5 mg) was given to female chimpanzees to determine the effect on endogenous sex hormone levels and anogenital swelling. Serum levels of EE2 increased with increasing dosages of EE2, estradiol decreased, and luteinizing hormone, progesterone and testosterone were maintained at approximately midfollicular phase levels. Urinary levels of EE2 glucuronide increased with the increasing dosages of EE2, whereas estrone and pregnanediol glucuronide were essentially undetectable. The cyclic increase in female anogenital swelling was abolished when the norethindrone was combined with 50 micrograms of EE2 and relatively constant and low levels of swelling were recorded. Relatively constant but successively higher levels of swelling were recorded when the norethindrone was combined with the higher dosages of EE2. These effects of oral contraceptives on female genital tissues are relevant to our laboratory studies of sexual behavior in chimpanzees given oral contraceptives and could also have implications for women taking oral contraceptives.

Anal Canal↗
PubMed1976

[Steroid receptors and hormonal receptivity. New pharmacological and therapeutic approaches applicable to the control of fertility].

The definition and main characteristics of the steroid hormone receptors are given. One may note a relationship between hormonal receptivity and the physiological changes in the concentration of the receptors in the target organs. The distribution of the various receptors is given in detail showing the existence of (a) different receptors for the same hormone in different target cells; (b) different receptors for different hormones in the same cells; (c) different receptors for the same hormone in the same cell. A new pharmacological approach is proposed based on differentiation of receptivities from which there results a dissociation of the therapeutic effects.

Drug Interactions↗
PubMed1976

Determinantion of testosterone concentration in semen of men with normal or subnormal sperm counts and after vasectomy.

Semen from 58 male subjects, aged 22 to 50, was assayed on an individual basis to determine whether T was present in it. Of the subjects examined 23 were normospermic, 14 oligospermic and 9 azoospermic; 12 men had undergone vasectomy were also included in the study. In 39 of the subjects plasma testosterone was estimated. A competitive protein binding technique was employed for T assays while dried extracts of semen were examined by combined gas-chromatography-mass spectrometry and mass fragmentography. Measurable amounts of T were detected in all seminal specimens assayed. This was confirmed by gas chromatography-mass spectrometry which showed a spectrum suggestive of T. The ratio of unconjugated to conjugated steroid in semen was found to be approximately 1:10. Levels of unconjgated T were similar to those found in plasma of normally menstruating women. The mean seminal concentration of unconjugated T (+/-SD) in the specimens assayed was 0.71 ng/ml+/-0.08 for the normospermic, 0.79+/-0.14 for the ezoospermic, 0.69+/-0.09 for the oligospermic, but only 0.38+/-0.04 for the vasectomized subjects. Plasma levels for this androgen were within the range found in normal men of comparable age. Significant correlation between plasma and seminal T concentration could not be demonstrated and there was no correlation between either of the above parameters and the seminal volume, the number, abnormal form percentage and the motility of spermatozooa in the normo--or oligospermic group. However, when the two groups were pooled into one, significant correlations were found between plasma, (but not seminal T concentration) and the seminal characters examined, perhaps suggesting the number of specimens from the groups should be increased to obtain valid data. Administration of human chorionic gonadotropin produced a marked plasma response as well as a rise of seminal T levels in 3 normospermic subjects whereas cyproterone acetate caused reduction of plasm T levels but had no consistent effect on the seminal concentration of ts steroid although the sensitivity of the seminal method may not have detected smaller changes at this level.

Adult↗
PubMed1975

Correlation between follicle stimulating hormone, luteinizing hormone, testosterone and 5-hydroxyindole acetic acid with sperm cell concentration.

Plasma follicle stimulating hormone, luteininzing hormone, testosterone, urinary 5-hydroxyindole acetic acid and 17-ketosteroids were measured in patients seen at an infertility clinic. Plasma folicle stimulating hormone and luteinizing hormone levels, and urinary 5-hydroxyindole acetic acid levels were increased in patients with sperm concentrations less than 10 times 10(6) per ml. Plasma testosterone levels were lower in patients with sperm concentrations less than 10 times 10(6) per ml. The results suggest that in patients with sperm counts less than 10 times 10(6) per ml. there is not only impaired spermatogenesis but also decreased Leydig cell function. Urinary 17-ketosteroid levels were not related to sperm cell concentration.

17-Ketosteroids↗
PubMedDate not supplied

[Steroidogenic function of the intra-arterial trophoblast in the rat. Ultrastructural, histoenzymologic and biochemical data].

The ultrastructural study of the intra-arterial trophoblast has revealed in the pregnant Rat a steroidogenic activity which has been confirmed by histoenzymologic observations (presence of delta 5-3 beta-HSDH and 17 beta-HSDH). At the 15th day postcoitum an in vitro investigation upon the metabolism of steroid hormone precursors suggests that the steroids (oestrogens, progestogens and androgens) secreted by the intra-arterial trophoblast have a local action upon the wall of the uterine placental arteries and are actively concerned with an important part upon the utero-placental hemodynamic as a whole.

Androstenedione↗
PubMed1975

Role of carbohydrate of human chorionic gonadotropin in the mechanism of hormone action.

The role of the carbohydrate part of human chorionic gonadotropin (hCG) was investigated by measuring the ability of hCG derivatives lacking various sugar residues to bind to rat Leydig cells and stimulate them to synthesize testosterone and cyclic adenosine 3':5'-monophosphate (cyclic AMP). Whereas sequential removal of the sialic acid, galactose, N-acetylglucosamine, and mannose residues led to a progressive increase in the effective dose of the hormone required to stimulate steroidogenesis, it resulted in a marked loss in the ability of the hormone to stimulate cyclic AMP accumulation. Low doses of the glycosidase-treated hormone derivatives were additive with hCG when their ability to stimulate testosterone synthesis was analyzed. Nevertheless, the glycosidase-treated derivatives were potent inhibitors of hCG-induced cyclic AMP accumulation, suggesting that removal of the sugars did not influence binding of the hormone to the cell as much as it reduced the ability of the bound hormone to activate adenyl cyclase. This hypothesis was further supported by our finding that the hCG derivatives were highly effective inhibitors of 125I-hGC binding to the intact cells. Removal of sialic acid and galactose enhanced the inhibition, whereas removal of all the sugar residues only decreased the inhibition slightly. The degree of these effects was comparatively small. The possibility that steroidogenesis and cyclic AMP accumulation are altered independently by hCG stimulation is discussed.

Acetylglucosaminidase↗
PubMed1977

Gonadal function following vasectomy in the rat.

Adult rats were studied at four, eight, and 12 months following vasectomy and sham-operation. The weights of the seminal vesicles, ventral prostate, pituitary, and kidneys were not significantly affected by vasectomy. Testicular endocrine function in vasectotomized rat was transiently stimulated as witnessed by elevation in testicular venous testosterone and androstenedione after four months. There then occurred signs of decline in gametogenic function and atrophy of the testis after 12 months whereas hormonogenesis appeared to remain at normal levels. There was no alteration in the morphology of the epididymis at any of the time intervals of study after vasectomy.

Animals↗
PubMedDate not supplied

Treatment of hirsutism related to micropolycystic ovary syndrome (MPCO) with two low-dose oestrogen oral contraceptives: a comparative randomized evaluation.

In order to evaluate the clinical and endocrinological efficacy of two low-dose oral contraceptives (OC) containing 30 micrograms Ethinylestradiol (EE) and 150 micrograms Desogestrel (DG) and 75 micrograms Gestodene (GD), respectively, an open randomized study was carried out in 34 young hirsute women, matched for body mass index and age. All of them met endocrine and ultrasonic criteria for Micropolycystic Ovary Syndrome (MPCO). The participants were randomly assigned to one of two pill groups (each of 17). The serum values for Total Testosterone (TT), Free Testosterone (FT), Androstenedione (A), Dehydroepiandrosterone (DHEA), Dehydroepiandrosterone Sulphate (DHEAS), 17-Hydroxyprogesterone (17Pg), Sex Hormone Binding Globulin (SHBG), Ceruloplasmin (CP), as well as Ferriman-Gallwey Index (FGI) and Free Androgen Index (FAI) were evaluated prior to and after EE-DG and EE-GD 6 cycle treatment. A significant decrease in TT, FT, A, 17Pg, DHEA, DHEAS, FGI, FAI was observed, SHRG and CP increased significantly. There were no significant differences between the two OC. Our results seem to indicate that both OC are equipotent as far as their pharmacological profile and residual androgenic activity are concerned. Therefore, these OC may represent a highly effective and suitable alternative to the treatment of hyperandrogenism related to MPCO.

17-alpha-Hydroxyprogesterone↗
PubMed1975

Clinics in endocrinology and metabolism. Investigative procedures.

In patients with hypogonadism, the exact cause of the deficient androgenisation is not always clinically apparent. The data presented demonstrate that by means of hormone measurements, basally or after stimulation tests, the exact level of the lesion can usually be determined. This allows a decision with regard to appropriate therapy to be made on the basis of an accurate diagnosis. In many instances basal measurements of pituitary and gonadal hormones are all that is required to decide the level of the lesion. Care in interpreting basal levels is required, however, in view of methodological limitations and of known physiological variations with age, time of day and hour-to-hour fluctuations. If the basal hormone levels are borderline, or if the 'reserve function' of part or all of the hypothalamic-pituitary-gonadal axis needs to be assessed, than the appropriate stimulation test should be performed. The indication for these stimulation procedures and results obtained in different conditions are described and problems of interpretation discussed.

Adult↗
PubMed1975

An apparently direct inhibitory effect of oestrogen on the human testis.

In men suffering from prostatic cancer, i.v. administration of 12 g diethylstilboestrol diphosphate within 20 days resulted in a decrease of the LH serum level to about 50% (P less than 0.05), whereas the total testosterone level decreased to less than 5% (P less than 0.001) and the apparently free testosterone level to less than 2% of the initial values (P less than 0.001). Hence, the "systemic antiandrogenic effect" of oestrogen can be explained (1) by indirect inhibition of testicular androgen secretion via diminution of hypophyseal gonadotrophin secretion, (2) by direct inhibition of testicular androgen secretion and (3) by elevation of the capacity of testosterone binding beta-globulin.

Aged↗