Age-reletad changes in the diabetic alterations of the hypohysis-thyroid-testicular axis in male rat

RESUMO

The effects of streptozotocin diabetes on the male reproductive tract were studied in young rats in different ages (25 to 60 days old). The data showed that diabetes caused atrophy of pituitary, testes and sexual accessory glands as well as testicular and pituitary functions, as evaluated by the circulating levels of LH and testosterone. In addition, an impairment of thyroidal function was detected since thyroxine serum levels were decreased. It is also seen that prolactin levels were reduced as a consequence of streptozotocin treated rats. Since younger animals were more drasticaly affected, we conclude that hypothyroidism that follows after the onset of diabetes could contribute to the picture on the basis of the importance of thyroidal function in the developing animal. Also it seems that reduction of prolactin levels due to hypothalamic TRH impairment would bring about a lack of the so important sinergistic action of this hormone and androgens in maintenance of androgen targetorgans.