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Biomedical subjects

A R Sheth

Publications and source records attributed to A R Sheth.

At least 127 records · Page 7Linked to original sources
PubMed1982

Effect of testosterone, estradiol-17 beta, and 5 alpha-dihydrotestosterone on inhibin production by sertoli cells in culture.

Inhibin activity in charcoal-extracted spent culture medium of Sertoli cells in Primary culture (CSCCM) was monitored by following the temporal inhibition of serum levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) in normal adult male rats. Subcutaneous injection of CSCCM reduced LH and FSH levels within 15 min and maintained the inhibition up to 10 hr. No selective suppression of FSH was observed. The model was used to assess inhibin activity in CSCCM from Sertoli cell cultures incubated with 5 alpha-dihydrotestosterone (DHT), testosterone (T), and estradiol -17 beta (E2) (5 micrograms/ml) for 24 hr. CSCCM from T and E2 treated groups suppressed gonadotropins while the group exposed to DHT failed to elicit any inhibition. DHT seems to inhibit the release of inhibin by Sertoli Cells.

Animals↗
PubMed1981

Effect of inhibin on ovulation and implantation in mice.

Injection of antiserum to ovine FSH on the day of proestrus could inhibit ovulation in the next cycle. Inhibin preparation purified from sheep ovaries failed to affect ovulation in mice. Suppression of FSH by this preparation of inhibin during early pregnancy reversed the mitotic index. Administration of inhibin during the peri-implantation period terminated pregnancy in mice. The inhibin preparation decreases FSH in circulation which in turn may possibly reduce ovarian estrogens, thereby inhibiting pregnancy.

Animals↗
PubMed1981

Biological studies with low and high molecular weight inhibin preparations.

The effects of both high and low molecular weight inhibin preparations on testicular and pituitary receptors were studied. Both these preparations were able to inhibit the binding of labelled hFSH to testicular receptor in a dose related manner, but were unable to affect the binding of labelled hCG to its receptor, suggesting that the observed inhibition of FSH binding was specific to inhibin. In addition, the binding of LHRH to pituitary receptors was affected by inhibin preparations. Interestingly, the antiserum raised against high molecular weight inhibin was able to neutralize, totally, the biological effect of high molecular weight inhibin, and only, partially, the biological effect of low molecular weight inhibin.

Animals↗
PubMed1981

Ectopic human placental lactogen and beta-human chorionic gonadotropin in gastric fluid of patients with malignant and non-malignant conditions of the stomach.

Human placental lactogen (hPL) and beta-human chorionic gonadotropin (beta-hCG) in gastric aspirates and sera of 24 patients with malignant (12 patients) and non-malignant (12 patients) conditions of the stomach were studied. In patients with cancer of the stomach, hPL and beta-hCG were found to be present in gastric aspirate at higher frequency than in serum. The concentration of these hormones in gastric aspirate was higher than in serum. In 2 patients with duodenal ulcer beta-hCG was found to be present in gastric aspirate, 1 of them having the hormone in circulation as well, while none of the 12 patients with non-malignant conditions of the stomach showed presence of hPL in their gastric aspirate or serum.

Adult↗
PubMed1981

Inhibin in the human prostate.

"Inhibin"-like protein, partially purified from the human prostate, was similar to that obtained from human seminal plasma under identical conditions. Concentration of inhibin in human prostate was tenfold higher as compared to human testis and was active biologically and immunologically. The presence of a high amount of inhibin in prostate seems to be unique in humans. Further inhibin concentration in benign prostatic hypertrophy tissue increased by tenfold in comparison to normal or cancerous tissue. Hence determination of serum level of inhibin may be used as a therapeutic tool to monitor prostate diseases.

Animals↗
PubMed1981

Selective suppression of FSH as a possible approach for fertility regulation.

Inhibin can exist in multiple forms. The size heterogeneity of inhibin (low and high molecular weight) is likely to be due to the purification procedures employed. However, irrespective of their size, both inhibin preparations are capable of suppressing circulating FSH levels. Since inhibin is a native hormone, the toxic effects after therapeutic administration are expected to be minimal. Inhibin is able to suppress only 70%-80% of the FSH secretion. Inhibin and the steroid (estrogen or androgen) may be involved in the physiological regulation of FSH. To completely suppress circulating FSH, administration of either a combination of inhibin and a steroid or a potent synthetic analogue of inhibin may be necessary. Inhibin has a very short half life in the adult animal, which may be due to the involvement of other testicular factors. Identification and characterization of these factors may help in prolonging effectiveness of inhibin.

Animals↗