Abstract: This study was aimed to explain the functional role of the mediation in the organs of the male reproductive system (prostate and seminal vesicles of rat and hamster), representing through the visualization of adrenergic fibres (Falck method), cholinergic fibres (Martinez-Rodriguez method) and by immunohistochemical methods to detect the P substance and the CGRP (PAP) in glandular structures. The adrenocholinergic and peptidergic mediators have a growing interest for their synergic action in the control of contractility, vasodilatation and most likely, of the secretory activity of the epithelium, probably expressed by endocrine-paracrinous mechanisms.