Abstract

Abstract Prenatal stress is considered as an early epigenetic factor able to induce long‐lasting alterations in brain structures and functions. It is still unclear whether prenatal stress can induce long‐lasting modifications in the hypothalamo‐pituitary‐adrenal axis. To test this possibility the effects of restraint stress in pregnant rats during the third week of gestation were investigated in the functional properties of the hypothalamo‐pituitary‐adrenal axis and hippocampal type I and type II corticosteroid receptors in the male offspring at 3, 21 and 90 days of age. Plasma corticosterone was significantly elevated in prenatally‐stressed rats at 3 and 21 days after exposure to novelty. At 90 days of age, prenatally‐stressed rats showed a longer duration of corticosterone secretion after exposure to novelty. No change was observed for type I and type II receptor densities 3 days after birth, but both receptor subtypes were decreased in the hippocampus of prenatally‐stressed offspring at 21 and 90 days of life. These findings suggest that prenatal stress produces long term changes in the hypothalamo‐pituitary‐adrenal axis in the offspring.