Enhanced effect of chronic stress on pregnancy outcome in Uje:WIST rats by prenatal treatment with lithium.

Female Uje:WIST rats were exposed to lithium (20 mmol LiCl/l drinking water, lithium levels about 1 mmol/l serum) for at least three weeks before mating and continuously up to the end of gestation. Female F1-offspring were raised without further treatment and mated at an age of 90-120 days with untreated males. The effect of chronic restraint stress during gestation on pregnancy outcome was estimated. Moderate changes (higher frequency of prolonged gestation, decreased body mass of the newborn pups) resembled those which were induced by considerably longer stress exposure (extended to the premating period) of prenatally untreated female Uje:WIST rats. An enhanced stress sensitivity following prenatal lithium treatment is discussed.