Adrenal steroidogenesis following prenatal dexamethasone exposure in the spiny mouse

Antenatal stress disturbs the development of the fetal hypothalamic-pituitary-adrenal axis and adrenal steroidogenesis. We investigated the effect of brief maternal exposure to high glucocorticoids (dexamethasone (DEX)) at mid- and late-pregnancy on adrenal structure and production of steroids in spiny mouse. Pregnant spiny mice were treated for 60 h with 125 mug/kg DEX or saline s.c. by osmotic minipump at day 20 (0.5) or 30 (0.75) of gestation. Immunohistochemical expression of steroidogenic acute regulatory-protein (StAR), 3beta-hydroxysteroid dehydrogenase (3betaHSD), 17-hydroxylase,17-20lyase (P450C17), and cytochromeb5 (CYTB5) was determined in adrenals on postnatal (P) day 170+/-20. DHEA, testosterone, and cortisol were measured by RIA. Maternal DEX at 20 days significantly reduced the expression of STAR, P450C17 (CYP17A1), and CYTB5 in the adrenal zona reticularis (ZR) of adult offspring, with greater change in male vs female offspring (P