THE ADRENAL FETAL ZONE: ITS OCCURRENCE IN PRIMATES AND A POSSIBLE RELATIONSHIP TO CHORIONIC GONADOTROPIN1

Abstract

A fetal zone was found in the adrenal glands of some newborn primates (chimpanzee, Congo potto, marmoset) but not others (cercopithecus hybrid monkeys, slow loris). A fetal zone was found during fetal life in the macaque, this zone disappeared before birth by transition into adult-type cortex. This finding affords an explanation for the unexpected variations in adrenals of various newborn primates. It also suggests a functional relationship between fetal zone cells and those of the adult cortex. There is evidence that chorionic gonadotropin is responsible for the development and maintenance of the fetal zone, probably by influencing the intensity of the adrenotropic stimulus from the fetal pituitary.