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Updated: Sep 27, 2026

Bladder Smooth Muscle Strip Contractility as a Method to Evaluate Lower Urinary Tract Pharmacology
Published on: August 18, 2014
[Inhibition of tonic contraction of smooth muscle: a new approach to achieve erection dysfunction]
Yu-Tian Dai1, Thomas M Mills, Ronald W Lewis
1Department of Urology, Affiliated Drum Tower Hospital, Nanjing University School of Medicine, Nanjing, Jiangsu 210008, China.
Abstract:
It has shown that vasoconstriction in the cavernosal circulation is mediated by the RhoA/Rho-kinase calcium sensitization pathway. Inhibition of Rho-kinase activity in cavernosal smooth muscle with Y-27632 resulted in an erectile response marked by elevated intracavernosal pressure (ICP) without a significant change in men arterial pressure (MAP). To explain how erection can occurred in the presence of this strong vasoconstrictive signal, we have hypothesized that nitric oxide (NO) induces vasodilation leading to erection by directly inhibiting activity of the RhoA/Rho-kinase pathway, thereby reducing vasoconstriction. Administration of Y-27632 restored erectile function in rat models of hypogonadism and hypertension, suggesting that Rho-kinase inhibition may have potential clinical value. In addition, our results show that topical application of Y-27632 may be an effective mode of treatment for erectile dysfunction.
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