INDUCTION OF ATYPICAL PROSTATIC HYPERPLASIA IN RATS BY SYMPATHOMIMETIC STIMULATION

BACKGROUND. Prostatic innervation may participate in its homeostasis a nd growth, alpha-Adrenergic inhibition alleviates clinical symptoms in benign prostatic hyperplasia. However, the prostatic effect of adrene rgic agonists has not been investigated. This study deals with the pro static effect of subchronic sympathomimetic stimulation. METHODS. Male rats received daily subcutaneous injections of the alpha-adrenergic a gonist phenylephrine, 1, 10, or 20 mg/kg per day, the beta-adrenergic agonist isoproterenol, 1, 2.5 or 5 mg/kg per day, or saline, for 30 da ys, and the prostates were removed for histopathological examination. RESULTS. Phenylephrine induced atypical prostatic hyperplasia, charact erized by piling-up with papillary and cribriform patterns, and buddin g-out of epithelial cells. It decreased prostatic secretions and total weight. Similar results were observed in orchidectomized rats receivi ng exogenous testosterone supplementation. Isoproterenol had no prosta tic morphological effect. CONCLUSIONS. These results raise the possibi lity that sympathetic stimuli play a role in normal and aberrant growt h and differentiation of prostatic epithelium, and suggests neurostimu lants-treated animals as a model to study the etiology and development of prostatic hyperplasia. (C) 1998 Wiley-Liss, Inc.