Effect of acute and chronic stress on testosterone secretion in male rats.

The effect of acute and chronic stress on serum testosterone was studied in adult male Wistar rats. Acute noise-light stress and the presence of a dog, but not change of room, raised serum testosterone. This testosterone was of gonadal origin since noise-light stress did not increase serum testosterone in castrated rats. Chronic noise-light did not modify either testes weight or serum testosterone. This suggests that chronic stress did not necessarily lead to impairment of endocrine function of the testes in the rat.