Spermatogenic and steroidogenic testicular function in hypothyroid pubertal rats.

The reproductive system of immature rats is held to be more influenced by thyroid dysfunction than that of adult animals. The effect of hypothyroidism on the spermatogenic process of the rat has not been reported previously. The objective of the present study was to investigate the spermatogenic and steroidogenic functions of pubertal hypothyroid rats. Hypothyroidism was induced by ad libitum ingestion of a 0.05% solution of propylthiouracil for 60 days, and confirmed by reduced plasma thyroxine levels in treated rats. Plasma testosterone level, the histological features of the testis and cauda epididymis and the concentration of spermatozoa stored in the cauda epididymis were unchanged by hypothyroidism.