Bladder and urethral function in a mouse model of cavernous nerve injury

Abstract

To determine whether cavernous nerve injury (CNI) alters lower urinary tract function, we assessed bladder and urethral function over time in a mouse model of CNI. Twelve-week-old male C57BL/6 mice were divided into three groups: unoperated (UO; n = 6), sham-operated (SO; n = 18), and bilateral CNI (n = 30) group. At 1, 2, 4, 6, 8, 10 days bladder and urethral function were evaluated in these three groups using cystometry (CMG) and leak point pressure (LPP) recording under anesthesia. There was no significant difference in maximum detrusor pressure between groups at all times. Compared with the UO group, bladder compliance, and capacity in the CNI group were significantly decreased at Days 1, 2, 4 (P < 0.05) and recovered gradually from Day 6 to Day 10. In the SO group, they were decreased at Day 1, however, recovered more rapidly than the CNI group. Non-voiding contractions (NVC) developed in the CNI group at all times. Intercontraction interval were significantly decreased in SO and CNI groups and recovered more rapidly in SO group. In the SO group NVC were observed only at Days 1 and 2. LPP in the CNI group was decreased significantly at Days 1 and 2 (P < 0.05) and rapidly recovered with time compared with the UO and SO groups. In a mouse model of CNI, a transient decrease in bladder compliance, capacity, LPP and increased NVC was observed. These changes gradually recovered from Day 6 after CNI. Our findings suggest that CNI may affect bladder and urethral function, but alterations are reversible.