Impact of surgical bladder catheter implantation on voiding function in mice

Lower urinary tract (LUT) disorders significantly impact quality of life, yet treatment advancements remain limited. Animal models, such as those using invasive urodynamics with surgically implanted suprapubic bladder catheters, are vital for preclinical research. However, the effects of catheter implantation on bladder function have not been well characterized. The primary objective of this study was to evaluate the impact of surgical bladder catheter implantation on voiding function in male and female mice by comparing noninvasive voiding behavior before and after bladder catheter implantation in the same animals. We assessed voiding parameters in 16 mice (n = 7 male and n = 9 female) before and after catheter implantation using noninvasive voiding assays conducted in a home-cage environment. These assessments revealed significant changes in postimplantation voiding behavior, characterized by increased void frequency (P = 0.0004) and decreases in both void volumes (P < 0.0001) and intermicturition intervals (P = 0.0006). Urodynamic studies further demonstrated that bladder capacities were reduced 10%-30% compared with preimplantation estimates, reflecting physical reductions in bladder volume caused by the catheterization procedure. Similar results in the voiding function were seen in both male and female mice. These findings demonstrate that surgical catheter implantation alters voiding function, with overall consistent effects observed across sexes. The observed changes likely result from physical bladder size reduction due to catheter placement and the use of a purse-string suture to secure the catheter. This study underscores the importance of accounting for procedural artifacts in preclinical LUT research to ensure translational relevance.NEW & NOTEWORTHY This study provides the first characterization of voiding behavior and bladder function changes following surgical bladder catheter implantation in mice, as measured using noninvasive assays. We show that surgical catheter implantation reduces bladder capacity and significantly alters voiding parameters, including frequency, volume, and intermicturition intervals, with overall consistent effects across sexes. These findings highlight the importance of accounting for procedural artifacts when interpreting LUT function in preclinical models, ensuring translational relevance for future studies.