Effects of Streptozotocin-Diabetes and Insulin Replacement on Androgen and Estrogen Receptor Concentrations in the Epididymis of Wistar Rats

Abstract

The present study was aimed at evaluating the effects of streptozotocin (STZ)-induced diabetes and insulin replacement on the androgen (AR) and estrogen receptor (ER) concentrations in the caput, corpus and cauda epididymides of prepubertal and adult Wistar rats. Prepubertal (40 days old) and adult (120 days old) male Wistar rats were made diabetic by single intraperitoneal (i.p.) injection of STZ (120 mg/kg and 60 mg/kg body weight, respectively). To one set of diabetic rats, insulin was administered daily at a dose of 3 U/100 g body weight, subcutaneously, in two equally divided doses at 8.00 AM and 6.00 PM. All the rats were killed on the 21st day of commencement of experimentation. The epididymis was dissected out and caput, corpus and cauda segments were separated, freed from spermatozoa and processed for AR and ER quantification. STZ-induced diabetes caused a marked decrease in both nuclear and cytosolic AR and ER concentrations in the caput, corpus and cauda epididymides. Insulin replacement circumvented the adverse effects of diabetes in a segment-specific manner. These findmgs emphasize the detrimental effects of diabetes and the importance of insulin in the maintenance of epididymal AR and ER concentrations in immature as well as adult rats.