Morphologic Changes in the Adrenal Glands of Fetal and Newborn Rats Following Administration of Glucocorticoids to the Mother During Pregnancy

Abstract

Summary Pregnant rats were given dexamethasone or corticosterone from the 12th to the 21st day of pregnancy. The fetuses were examined on the 18th, 19th, 20th and 21st day of pregnancy. Following spontaneous delivery further groups were examined on the 1st, 7th and 14th postnatal day. Adrenal weight and body weight were determined. The adrenals were also studied histologically. The number of nuclei/constant area and nuclear size in the zona glomerulosa and fasciculata were determined morphometrically. In addition histochemical studies of 3s-ol-dehydrogenase activity in the adrenal cortex were done. 1. The effects of glucocorticoid administration during pregnancy on the adrenal and body weight of the fetuses are dose-dependent. There is a distinct delay in development of adrenal and body weight in fetuses and newborns. The adrenals of the dexamethasone groups grow significantly slower than the corticosterone groups that also show a retardation of growth. There is no perinatal drop in weight in the dexamethasone groups. 2. Morphometric studies of adrenal cortex pre- and postnatally show higher number of nuclei/constant area in zona glomerulosa and fasciculata indicating smaller cells. This finding is more pronounced in the dexamethasone than in the corticosterone groups. The nuclear diameters of cells of glomerulosa and fasciculata are diminished in the dexamethasone groups. Thus the nuclei show an atrophy. In the corticosterone groups on the other hand the nuclei in both cortical zones are almost always larger. Up to now we cannot explain this finding. 3. Both in controls and in treated groups numerous pathologic mitoses are found in adrenal cortical cells. This finding has not been described up to now and requires further quantitative and qualitative analysis. 4. The activity of 3s-ol-dehydrogenase in the adrenal cortex of fetuses and newborns is not influenced by glucocorticoid administration.