Correlation Between Nitric Oxide and Urodynamics in Men With Bladder Outlet Obstruction

Purpose: To investigate the correlation between nitric oxide (NO) and urodynamics in men with bladder outlet obstruction (BOO) by analyzing nitric oxide synthase (NOS) in the urothelium. Methods: We prospectively enrolled 25 men who planned to undergo surgical treatment for benign prostatic obstruction and identified as BOO in the preoperative urodynamics. Bladder tissue was taken during surgical prostate resection. Expressions of endothelial NOS (eNOS), inducible NOS (iNOS), and neuronal NOS (nNOS) in the urothelium were analyzed, and their correlation with urodynamic parameters was also assessed in all patients. We also compared the expressions of eNOS, iNOS, and nNOS between BOO with detrusor underactivity (DU) group and BOO without DU group. Results: In all patients, the level of eNOS positively correlated with maximal flow rate and with maximum cystometric capacity (MCC). The level of iNOS positively correlated with MCC. nNOS levels were positively correlated with detrusor pressure at maximal flow and with bladder contractility index in all patients. The level of eNOS, iNOS, and nNOS did not significantly differ between BOO without DU group and BOO with DU group. Conclusions: This study suggests that NO was correlated with bladder dysfunction in men with BOO. Particularly, nNOS may reflect the change in detrusor function.