AN INCREASE OF NEUROPEPTIDE-Y BUT NOT NITRIC-OXIDE SYNTHASE-IMMUNOREACTIVE NERVES IN THE BLADDER NECK FROM MALE-PATIENTS WITH BLADDER NECK DYSSYNERGIA

Purpose To determine the distribution of neuropeptides in male patient s with bladder neck dyssynergia and benign prostatic hyperplasia. Mate rials and Methods: Bladder neck tissue, obtained from male patients wi th bladder neck dyssynergia (END) and control patients with benign pro static hyperplasia (BPH), was studied immunohistochemically for protei n gene product 9.5 (a general neuronal marker), vasoactive intestinal polypeptide, neuropeptide Y, calcitonin gene-related peptide, substanc e P, growth associated protein 43 and nitric oxide synthase. Results: In the bladder neck from control patients, the greatest density of ner ves contained protein gene product 9.5, followed in decreasing order b y neuropeptide Y; vasoactive intestinal polypeptide; calcitonin gene-r elated peptide; nitric oxide synthase; substance P and serotonin. The neuropeptides were found in the smooth muscle and were also associated with blood vessels. In patients with END there was a statistically si gnificant increase (P < 0.05) in the density of protein gene product 9 .5- and neuropeptide Y-immunoreactive nerves in the smooth muscle and the base of the mucosa but not in blood vessels in the bladder neck, w hile the density of the other neuropeptides studied, nitric oxide synt hase and serotonin did not significantly change from that of control t issue. Growth associated protein 43-immunoreactive nerves were absent from the bladder neck from both groups of patients. Conclusion: It is suggested that the increase in density of protein gene product 9.5- an d neuropeptide Y-immunoreactive nerves, part of the sympathetic contra ctile system of the bladder neck, may exacerbate bladder outlet obstru ction and thus play a role in the pathogenesis of BND.