Experimental diabetes has adverse effects on the differentiation of ventral prostate during sexual maturation of rats

Diabetes mellitus of both type I (insulin-dependent) and type II (noninsulin-dependent) has adverse effects on male sexual and reproductive functions in adolescent boys and men, which include impairment of spermatogenesis, reduced sperm count, serum testosterone and seminal fluid volume, impotency, and loss of libido. Streptozotocin (STZ)-induced diabetes in rats provides a relevant model to study reproductive dysfunction under diabetic conditions, as they exhibit a number of deficits in reproductive function that resemble those seen in human diabetics. Therefore, the present investigation is aimed to understand the effects of STZ diabetes on the structure and development of ventral prostate during the critical period of sexual maturation in rats. Prepubertal (40-days-old) male Wistar rats were made diabetic by single injection of STZ (120 mg/kg body weight, intraperitoneally). Induction of diabetes was confirmed by serum insulin titer, hyperglycemia, and polyuria. To another set of STZ-diabetic rats, after 3 days of diabetes induction, insulin was replaced at a dose of 3 U/100 g body weight, subcutaneously in two equally divided doses at 8:00 AM and 6:00 Pm. Diabetes caused regression of prostate, leading to a decrease in the absolute weight. Histologically, glandular epithelium has undergone shrinkage with transformation of acinar cells into low cuboidal type with less prominent secretory granules and blebs. Nevertheless, the secretory activity was not totally abolished. Interstitial space was increased due to shrinkage of glandular epithelium. Histomorphometric studies on the tubular diameter, volume and surface density of acinar epithelium, lumen, and stroma also support regressive changes in prostate. Insulin replacement prevented the detrimental effects of diabetes partially. These findings implicate the adverse effects of STZ diabetes on the differentiation of ventral prostate during sexual maturation. (c) 2005 Wiley-Liss, Inc.