Effect of emotional stress experienced by female rats before pregnancy on brain development in their offspring.

Twenty-one- and 40-day-old offspring from female rats exposed to emotional stress for 3 weeks and mated with intact males 10 days later were examined. Intact female offspring served as the control. The weight of the brain of 21- and 40-day-old experimental rats varied is a wider range compared to the control. In 40-day-old experimental males, the mean weights of the brain and hemisphere were lower than in controls. In 21-day-old rats, layer V neuronal nuclei were enlarged, while the thickness of the parietal cortex tended to decrease. In 40-day-old animals, morphometric parameters of neurons in the neocortex and hippocampus and RNA concentration in their cytoplasm did not differ from the control. Thirty-day-old experimental rats demonstrated low exploratory activity in the plus-maze test.