Decidua and placenta in mice after treatment with a synthetic glucocorticoid

To investigate a possible long-term effect of glucocorticoids on decidua and placenta of mice, a single dose of 24 mg kg-1 body weight triamcinolone acetonide in crystalline suspension was given subcutaneously to NMRI mice on gestational day (GD) 2. Deciduae and placentae, as well as corticosterone and triamcinolone concentrations in maternal plasma of GDs 10 and 17 were examined. NADPH-cytochrome P450 reductase involved in drug biotransformation was detected immunocytochemically and showed co-localization with NADPH diaphorase histochemistry in the decidua and placenta. Both reactions were higher in endothelial cells of decidual sinusoids on GD 10, but were lower on GD 17 in the trophoblast, spongiotrophoblast and extraplacental visceral yolk-sac epithelial cells of treated mice than in untreated animals. Histochemistry of 11 beta-hydroxysteroid dehydrogenase, an enzyme that metabolizes biologically active adrenocortical steroids and their synthetic congeners in the placenta, showed higher activity on GD 17 in enlarged labyrinthic trophoblast I cells of treated mice than in untreated animals. As corticosterone concentrations were still decreased on GD 17, when triamcinolone concentrations were no longer detectable, a long-term suppression of adrenal gland function seems obvious.