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Bladder Smooth Muscle Strip Contractility as a Method to Evaluate Lower Urinary Tract Pharmacology
Published on: August 18, 2014
Contractile properties of the denervated external anal sphincter
1Division of Female Pelvic Medicine and Reconstructive Surgery, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
Objective:
The purpose of this study was to evaluate the effect of denervation on contractile properties of the external anal sphincter (EAS) of the female rat.
Study Design:
Sham operation, pudendal nerve transection, pelvic neurectomy, or combined pudendal nerve transection/pelvic neurectomy was performed in young female rats. Contractile function of the EAS was determined after 2 weeks.
Results:
Maximal force-generating capacity of the EAS was not impaired by bilateral pudendal denervation or pelvic neurectomy. Twitch tension, however, was decreased, and fatigability increased after pelvic neurectomy. Combined bilateral pudendal nerve-transection plus pelvic neurectomy resulted in compromised force-generating capacity, decreased twitch tension, and increased fatigability of the anal sphincter.
Conclusion:
Subtle changes in EAS function are detectable after pelvic neurectomy, but not pudendal denervation. In contrast, combination pudendal and pelvic neurectomy resulted in severe compromise of EAS function. These data suggest that EAS function is relatively preserved unless injury occurs to > 1 source of innervation.
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