Svnthesis in Vitro of Steroids bv Human Fetal

Presumptive evidence for the production of steroids by the human fetal adrenal gland has accumulated during recent years. The studies involved mostly analysis of fetal adrenal tissue (14) or umbilical cord blood (5-8) for steroid content, the results of which did not unequivocally establish steroid synthesis by the fetal adrenal cortex. Lanman and Silverman (9) demonstrated the conversion of progesterone to corticoids by neonatal adrenal slices. With one exception (I), the several studies were carried out on fetuses during the last trimester of gestation or at term, a period of variable change in the morphology of the fetal adrenal. The human fetal adrenal cortex is distinguished by the presence of two histologically distinct zones; the definitive (adult) cortex and the fetal zone. The latter comprises about 80 per cent of the total adrenal volume during most of pregnancy (10). Whereas the adult cortex transiently diminishes in size at birth, the fetal zone degenerates rapidly beginning after birth. The separate capacities of these two tissues for steroid production have not been studied. This report describes the isolation and characterization of several steroids from incubations of human fetal adrenal slices with sodium 1-CY4-acetate, and the capacity of both the adult cortex and fetal zone to produce steroids.