Involvement of Insulin and Testosterone in the Reproduction of Streptozotocin Diabetic Rats

Streptozotocin diabetic rats were shown to be subfertile, which can be overcome by treatment with insulin plus hCG. In this study, we have shown that replacement of hCG by exogenous testosterone was enough for restoration of the accessory glands activity in contrast to its failure to preserve sparmatogenesis and restore fertility. A synergistic effect of insulin and testosterone in control of the male accessory glands was evident. Exogenous testosterone, insulin or both together improved only slightly the epididymal function as reflected in sperm motility and fertility capacity. The fertility rate of the diabetic rats (14%) treated with either insulin (22%), testosterone (40%), or both together (50%) was not as good as the synergistic effect of insulin and hCG. These results point to the beneficial effect of LH (by hCG) in the regulation of male fertility apart from its control on the activity of the Leydig cell function.