Ci, STEROIDS, 17a-HYDROXYCORTICOSTERONE AND A SODIUM RETAINING FACTOR IN HUMAN FETAL ADRENAL GLANDS1

Abstract

Adrenal tissue from normal, male and female human fetuses, from the 9th - 21st week of gestation, were analyzed for their C19 and C21 contents. Three C19 steroids were tentatively identified by paper chromatograDhic methods as being present in all sex and age groups: [DELTA] 4-androstene-3, 17-dione, de-hydroepiandrosterone, and [DELTA] 4-androstene-11[beta]-ol-3,17-dione. Cortisoi was detected in the tissue extracts from the 16.5 -21.0 week of gestation. Extracts from all groups, when analyzed for Na retaining activity by bioassay, were found to be active. The concentration of C19 steroids per gram of adrenal tissue decreased with advancing fetal age (from about 30 to 8 [mu]g/g tissue, without significant differences between the sexes. This decrease is ascribed to an (a) increased release by the adrenal gland, (b) reduced C19 steroid synthesis, or/and (c) larger adrenal weight increase than steroid synthesis. The ratio of androgenic to glucocorticoid steroid content varied from a magnitude of 100:1 for the 9.5 - 12.5-week-old fetal adrenals to 5 - 10:1 for the 16.5 - 21.0 week old fetal adrenals. It is suggested that the early fetal adrenal cortex synthesize primarily weak androgenic steroids and a Na-retaining factor similar to aldosterone. C19 steroid synthesis is considered to occur in the fetal zone with decreasing activity as fetal age advances. The hypothesis is advanced that the fetal and reticular zones are the sites of adrenal androgen production, and the fascicular and glomerular zones, respectively, the sites of glucocorticoid and mineralocorticoid synthesis, respectively.