Gonadal function in male offspring of pinealectomized female rats

Female rats were exposed to a short (6 L: 18 D) photoperiod from 21 days of age. On day 2 of gestation, animals were pinealectomized sham-operated. Lighting regimens were not changed during the course of the study. Male offspring of the 2 groups of rats were sacrificed on days 30, 42 and 49 after birth. Pinealectomy of the mother induced the following modifications: in 30-day-old offsprings, a decrease in prostatic weight and plasma dihydrotestosterone level; in 42-day-old rats, a decrease in prostatic weight, in testicular androstenedione and dihydrotestosterone content, and in plasma testosterone and dihydrotestosterone levels; in 49-day-old animals, decreased testicular and plasma testosterone and dihydrotestosterone levels. These results indicate that rat testicular function, after exposure to a short photoperiod beginning before conception, is decreased by maternal pinealectomy. The mother's pineal gland may play a part in the control of rat testicular function.