Functional and molecular alterations in a rat model of detrusor underactivity induced by bilateral pelvic nerve crush injury

To investigate the functional and molecular alterations in detrusor underactivity (DU) in a rat model of bilateral pelvic nerve crush injury. This study included 39 female Sprague-Dawley rats separated into three groups (sham, 2-week DU, and 4-week DU), with 13 rats in each group. A bilateral pelvic nerve crush injury was induced in each group to develop a DU model. Similarly, the sham group was identically prepared but without crushing nerves. Awake continuous cystometry was performed two weeks post-surgery in the sham and 2-week DU groups and four weeks post-surgery in the 4-week DU group (n = 7/each group). In another group of rats (n = 6/each group), the bladders were harvested for western blotting, and the expression of moesin, ezrin, and transthyretin in the bladders was evaluated. On cystometry, voided volume, post-void residual urine volume, bladder capacity, and number of non-voiding contractions were significantly higher in the 2- and 4-week DU groups than in the sham group. Furthermore, voiding efficiency was significantly decreased in the 2- and 4-week DU groups compared to that in the sham group. The expression of moesin in the bladder was significantly higher in the 2-week DU group than that in the sham group. The expression of transthyretin in the bladder was significantly higher in the 2- and 4-week DU groups than that in the sham group. The significant increase in the expression of moesin and transthyretin in the bladder in bilateral pelvic nerve crush injuries may be related to the pathophysiology of DU.