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Biomedical subjects

I Mowszowicz

Publications and source records attributed to I Mowszowicz.

At least 73 records · Page 4Linked to original sources

On the role of dihydrotestosterone in regulating luteinizing hormone secretion in man.

The effect of dihydrotestosterone [17 beta-hydroxy-5 alpha-androstone-3-one (DHT) in the negative regulation of LH was studied throughout 3 months of percutaneous administration of this steroid to six normal male volunteers and six patients with primary testicular hypogonadism. In addition, testosterone (T) was administered according to the same protocol to the six hypogonadal patients. Plasma T, DHT, estradiol, sex hormone-binding globulin, and LH levels were measured by RIA before and weekly during treatment. In normal men, plasma DHT rose regularly from 0.5 +/- 0.2 to 3.3 +/- 0.9 ng/ml after 3 months of treatment. Concurrently, T decreased from 5.5 +/- 2.0 to 2.9 +/- 0.3 ng/ml, and sex hormone-binding globulin levels decreased from 1.2 +/- 0.1 to 0.9 +/- 0.05 mg/liter. Mean basal LH levels remained stable between 1.9 +/- 1.3 and 3.1 +/- 1.1 mIU MRC, LH 68/40 per ml throughout treatment. In hypogonadal men after DHT treatment, basal LH levels were not suppressed. In contrast, after T administration, plasma LH decreased from 19.8 +/- 5.4 mIU/ml to normal levels (3.4 +/- 2.7 mIU/ml). From these studies, we conclude that 1) high levels of plasma DHT, maintained over a long period, were unable to lower plasma LH in either normal or hypogonadal patients, and 2) in contrast, during the same length of time, high levels of plasma T were perfectly capable of achieving feedback regulation of LH secretion. From these data, it seems unlikely that circulating DHT plays an important role in the physiological regulation of LH secretion.

Adult↗

Myometrial cells in primary culture: characterization and hormonal profile.

A method for primary culture of ovine myometrial cells is described. After dissection, myometrium of ewe uteri was digested in trypsin and collagenase. The cells were preplated for 1 h at 37 degrees C. The non-attached cells were grown in appropriate medium supplemented with 2% fetal calf serum. They had a doubling time of 3 days, reached confluency at 10 days and did not exhibit contact inhibition. Cultures were maintained up to 22 days. Characterization of the cells was achieved by electron microscopy, analysis of myosin in cell extracts and assessment of hormone sensitivity. The cells were found to contain myofilaments, characteristic of smooth muscle. A high content of myosin (6--13%) was demonstrated on SDS-polyacrylamide gel electrophoresis: this was confirmed by ATPase activity assay. Cells responded to estradiol stimulation by increased protein synthesis, and bound [3H]estradiol in a specific and saturable way. These results suggest that myometrial cells grown in primary culture should provide a useful model for studying the hormonal control of contractile protein synthesis.

Adenosine Triphosphatases↗

Urinary 5 alpha-androstane-3 alpha,17 beta-diol radioimmunoassay: a new clinical evaluation.

A rapid specific and reliable RIA for urinary 5 alpha-androstane-3 alpha,17 beta-diol (Adiol) is described using chromatographical purification and a specific antibody. Values are reported under some physiological and pathological conditions in 179 individuals. In 43 normal adult men, the mean (+/-SD) urinary Adiol excretion was 193 +/- 77 micrograms/24 h, and in 29 normal women it was 44 +/- 23 micrograms/24 h. These values are significantly different (P less than 0.01). In 49 hirsute women, urinary Adiol Excretion was elevated (137 +/- 51 micrograms/24 h) and significantly different from this value in normal women (P less than 0.01). The urinary Adiol excretion in 10 postmenopausal women was very low (less than 5 micrograms/24 h). In normal adult subjects, the theoretical contribution to urinary Adiol of the major secreted androgens was calculated. Whereas dehydroisoandrosterone and dehydroisoandrosterone sulfate yield the same amount of urinary Adiol in both sexes, testosterone is the main precursor of Adiol in men and androstenedione is the main precursor in normal premenopausal and hirsute women. However, the amount of Adiol recovered in the 24-h urine depends not only on the secretion rate of androstenedione and testosterone but is also related to the testosterone 5 alpha-reductase activity present in androgen target cells, especially in sexual skin.

Adolescent↗

[12 cases of polycystic ovary type 1 (Stein-Leventhal syndrome): complete hormonal study (author's transl)].

Twelve patients with clinic and anatomic features of polycystic ovary syndrome type 1 were investigated for gonadotropic and androgenic functions. Basal LH level was 3 times higher than in normal women in the beginning of follicular phase (16,2 +/- 3,0 mUI/ml). After LH-RH stimulation (100 microgram), peak LH level was excessively high (70 +/- 10 mUI/ml) whereas FSH was normal. Clomiphen citrate (100 mg X 5 days) was followed in all cases by temperature ascension and biologic evidence of luteinisation. Four pregnancies were obtained. Plasma androstenedione was elevated in most cases (320 +/- 30 ng/ml) with elevated urinary androstanediol (80 +/- 20 microgram/24 h.) These elevated levels were strikingly reduced in all cases after ethinyl-estradiol, 50 microgram X 20 days. Physiopathologic hypothesis consistent with these results are discussed.

Androstane-3,17-diol↗

[Benign breast diseases: hormonal studies in 125 cases (author's transl)].

The results of exploration of the corpus luteum in 125 patients with benign breast disease are analysed. In 109 patients, plasma oestradiol and progesterone were measured at various times during the hyperthermic phase of the menstrual cycle. The results obtained were compared with those obtained in normal women explored during the same phase of the cycle. The average daily values for plasma progesterone obtained in this group of 109 patients was significantly lower than that found in the normal women, whilst there was no change in oestradiol levels. In addition, 16 patients were studied daily throughout the period of hyperthermia. In 8 cases, there the hyperoestrogenism, with or without progesterone insifficiency of the corpus luteum. In all, secretory imbalance of the corpus luteum with a tendency to relative or absolute hyperoestrogenism was a constant finding in women with benign breast disease.

Adult↗

[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.

Adult↗

Inadequate corpus luteal function in women with benign breast diseases.

The corpus luteum function of 109 patients with benign breast disease was appreciated by way of plasma progesterone and estradiol determinations during the luteal phase. These patients had ovulatory cycles according to a biphasic basal body temperature curve; blood samples for plasma progesterone and estradiol estimation were collected between the first and the last day of the thermal plateau following the thermal nadir. Results obtained were compared to those observed in 50 normal ovulatory women. In the patients' group, the mean daily levels for progesterone ranged from 3.5 +/- 0.4 (SE) ng/ml to 8.1 +/- 3.8 (SE) ng/ml according to day of blood collection. These values are significantly different from the corresponding daily values observed in normal women. No significant difference was observed concerning plasma estradiol between patients and normal women. These findings indicate that women with benign breast disease have an inadequate corpus luteum function which may be secondary to an ovulation disorder. Pathophysiological implications resulting from this observation are discussed.

Adolescent↗

The effect of progestins on submaxillary gland epidermal growth factor: demonstration of androgenic, synandrogenic and antiandrogenic actions.

The effects of progestins (0.1, 1.0, 6-10 mg/day) alone and in combination with testosterone (0.1 mg/day) on immunoreactive epidermal growth factor (EGF) concentrations in submaxillary glands from normal and androgen-insensitive (tfm/y) mice were studied. Since androgens are known to stimulate increased EGF levels, the responses to progestins were interpreted as androgenic, synandrogenic or antiandrogenic if they simulated, potentiated or inhibited androgen response, respectively. Of the progestins studied, medroxyprogesterone acetate (MPA) caused the greatest androgenic response when given alone; 10 mg produced a greater than 40-fold increase of EGF over control values. Lesser responses were achieved when progesterone or megestrol acetate (Meg Ac) were given alone. Cyproterone acetate (Cyp Ac) had no androgenic activity when administered alone and acted as a potent antiandrogen at all doses used. Progesterone and Meg Ac had weak antiandrogenic activity. The only synandrogenic response elicited was with a high dose (10 mg) of progesterone caproate. Neither MPA nor progesterone alone had any effect on EGF levels in tfm/y mice. These patterns of response differ from those seen in mouse kidney. The data indicate that progestins as a class are capable of androgenic, synandrogenic and antiandrogenic action in the mouse submaxillary gland, but that no single progestin is capable of all three actions. Since tfm/y mice lack a functional androgen receptor, the absence of EGF response in these mice to progestins as well as androgens suggest that the action of progestins may be mediated by the androgen receptor in the submaxillary gland.

Androgens↗

[Hormonal function of the ovarian corpus luteum during benign mammary diseases].

Plasma progesterone and oestradiol levels were estimated in 54 women who were suffering from breast pathology. (There were 18 cases of benign breast dysplasia, 28 cases of cystic disease of the breast and 8 cases of adenofibromata.) All these women had menstrual cycles that were apparently ovulatory, and the blood sampling was carried out on the 4th day after the rise in the temperature plateau. By way of controls, the same estimations were carried out on 20 normal women of the equivalent age at the same stage of the raised plateau. The levels of plasma oestradiol in patients who had breast pathology (136 +/- 75 pg/ml) were not significantly different from those of normal women (120 +/- 50 pg/ml). On the other hand patients with mastopathies had a far lower level of progesterone in the phase of the cycle that was considered to be luteal (5-7 +/- 3-1 ng/ml) in comparison with normal women (13-2 +/- 3-5 ng/ml). From these results the conclusion can be drawn that women who have benign breast disease while they are active from the ovulation point of view show a defect in secretion of progesterone by the corpus luteum. This defect is an isolated one. The physiopathological implications derived from this observation are discussed.

Adenofibroma↗