Effect of thyroidectomy, and thyroxine and α2u-globulin replacement therapy on testicular steroidogenic and gametogenic activities in rats

Abstract

Abstract Adult male rats were thyroidectomized and killed after 22 days of treatment. Thyroidectomy lowered the weights of testes and accessory sex organs, decreased the activities of testicular Δ5-3β- and 17β-hydroxysteroid dehydrogenases (HSD), and diminished spermatogenesis, serum levels of testosterone and α2u-globulin. Supplementation with thyroxine at a dose of 5 μg/100 g body weight per day for 21 days or supplementation with α2u-globulin at a dose of 1·5 mg/rat per day for 21 days in thyroidectomized animals partially reversed the decrease in HSD activities and serum concentrations of testosterone and α2u-globulin, while spermatogenesis was restored to normal. The weights of testes and accessory sex organs were also reinstated after supplementation with thyroxine or α2u-globulin in thyroidectomized rats in comparison with thyroidectomized animals. It was concluded that α2u-globulin may be an intermediary in the thyroid hormone control of testicular function. Journal of Endocrinology (1994) 140, 343–347