IN VITRO STEROL AND STEROID SYNTHESIS BY OVARIES OF HYPOPHYSECTOMIZED IMMATURE RATS TREATED WITH HUMAN GONADOTROPHINS

• Published in: Acta endocrinologica (Copenhagen) Vol. 73; no. 2; pp. 321 - 334
• Main Authors: Bai, R U, Bischoff, K, Macome, J C, Diczfalusy, E
• Format: Journal Article
• Language: English
• Published: Denmark 01.06.1973
• Subjects: 17-Ketosteroids - biosynthesis; Acetates - metabolism; Androgens - biosynthesis; Androstenedione - biosynthesis; Animals; Carbon Isotopes; Cholesterol - biosynthesis; Chorionic Gonadotropin - pharmacology; Chromatography, Paper; Chromatography, Thin Layer; Estradiol - biosynthesis; Estrone - biosynthesis; Female; Follicle Stimulating Hormone - pharmacology; Gonadal Steroid Hormones - biosynthesis; Hypophysectomy; Luteinizing Hormone - pharmacology; Ovary - drug effects; Ovary - metabolism; Progesterone - biosynthesis; Rats; Sodium; Testosterone - biosynthesis; Tritium
• ISSN: 0804-4643; 0001-5598; 1479-683X
• DOI: 10.1530/acta.0.0730321

ABSTRACT The in vitro conversion of sodium [ 1,2- 14C] acetate into sterols and steroids was studied following the incubation of groups of ovaries from hypophysectomized immature rats with human gonadotrophins. Tritium labelled internal standards were used to monitor procedural losses and sterols and steroids were isolated in a radiochemically homogeneous form. The gonadotrophin preparations studied included a highly purified human urinary LH preparation (with no detectable FSH activity) as well as human urinary FSH and HCG preparations in which the LH and FSH-like activity, respectively, was selectively neutralized by the addition of appropriate antigonadotrophic sera. The ovaries of saline-treated control animals converted considerable quantities of labelled acetate into cholesterol and small amounts into cholesterol esters. Little, if any, acetate was converted by these ovaries into steroids. The injection of a human urinary LH-free FSH preparation or of a highly purified human urinary LH preparation resulted in a marked increase in the incorporation of labelled acetate into cholesterol, which was accompanied by a slightly increased incorporation into cholesteryl esters. Small amounts of carbon-14 labelled androstenedione and testosterone were also isolated but no pregnenolone or progesterone was found.