Inhibition of aromatase activity during pregnancy affects sex-related adrenocorticotropic hormone release in response to ether-inhalation in juvenile rats.

The pituitary release of adrenocorticotropic hormone (ACTH) induced by ether inhalation was investigated on day 30 postpartum in male and female young rats from mothers treated daily with the aromatase inhibitor ATD (1,4,6-androstatriene 3,17-dione) from day 17 to day 21 of gestation, in males from mothers injected daily with solvent during the same period of gestation. In spite of a surge in plasma testosterone levels at birth, the males from ATD-treated mothers showed on day 30 postpartum a pituitary response characteristic of the females and not of the males. Thirty minutes after the end of the ether inhalation, the males from ATD-treated mothers showed a surge in plasma ACTH similar to that of littermate females but significantly higher than that of males from solvent-treated mothers. These data suggest that the aromatization of endogenous testosterone to estrogens during the critical period of the fetal life, when a transient surge of plasma testosterone was observed, has a significant organizational effect on the sexually dimorphic ACTH response to the ether stress.