Neuropeptides in the seminal vesicles: locations, binding sites and functional implications

The importance of neuronal factors in the normal physiology of the seminal vesicles has been traditionally underestimated when compared to the trophic role of androgens. Immunohistochemical, autoradiographical and pharmacological experiments have, however, raised the possibility that neuropeptides, such as vasoactive intestinal polypeptide (VIP), neuropeptide tyrosine (NPY) and calcitonin gene-related peptide (CGRP), are necessary for full seminal vesicle function and development. These neuropeptides may be involved in the regulation of secretion, smooth muscle tone and blood flow. Furthermore, neuropeptides may have functional interactions with androgens affecting, probably, androgen receptor-dependent gene expression in these glands. It is now timely to focus attention on the biological relevance of neuropeptides in the seminal vesicles.