Effects of hyperprolactinemia on rat prostate growth: evidence of androgeno-dependence

Effects of hyperprolactinemia on rat prostate growth: evidence of androgeno-dependence. Am J Physiol Endocrinol Metab 280: E120-E129, 2001.--The effects of the polypeptide hormone prolactin (PRL) in the development and regulation of benign prostate hyperplasia (BPH) and also in prostate cancer are not very well characterized. This study examines the action of PRL, either alone or in association with androgens [testosterone (T) or dihydrotestosterone (DHT)], in the rat prostate gland. The effects of PRL and androgens were investigated after 30 and 60 days in control, castrated, castrated with a substitutive implant of T or DHT, and shamoperated Wistar rats. To enhance PRL release, we induced hyperprolactinemia by administering chronic injections of sulpiride (40 mg [multiplied by] [kg.sup.-1] [multiplied by] day-1). Chronic hyperprolactinemia induces enlargement and inflammation of the lateral rat prostate without any histological changes on ventral and dorsal lobes. We also demonstrate that hyperprolactinemia induces Bcl-2 overexpression in the lateral rat prostate and that this could inhibit the level of apoptosis. The in vivo model established here is a useful in vivo approach for studying the hormonal regulation of normal and pathological prostate development. prolactin; testosterone; dihydrotestosterone