Improved model for the establishment and evaluation of detrusor overactivity in female Wistar rats.

Abstract

OBJECTIVE: To improve the model for establishment and evaluation of detrusor overactivity in female Wistar rats. MATERIALS AND METHODS: We ligated the perineal urethra of female Wistar rats and then performed filling cystometry. The probability of detrusor overactivity, bladder capacity, peak voiding pressure and histological changes were investigated. RESULTS: Detrusor overactivity ratio of the obstruction group was 32.4%. Bladder capacity increased from 0.273 &#xb1; 0.036 mL in control group to 0.89 &#xb1; 0.19 mL in detrusor overactivity group (P < 0.001), and peak voiding pressure increased from 45.9 &#xb1; 4.1 cm.H2O to 63.5 &#xb1; 17.4 cm.H2O (P = 0.007). For obstruction group, compared to no detrusor overactivity rats, detrusor overactivity rats had higher bladder capacity (0.89 &#xb1; 0.19 mL versus 0.43 &#xb1; 0.09 mL, P < 0.001) and higher peak voiding pressure (63.5 &#xb1; 17.4 cm.H2O versus 44.8 &#xb1; 6.2 cm.H2O, P = 0.005). Detrusor overactivity rats were classified according to peak voiding pressure (49.2 &#xb1; 4.2 cm.H2O versus 80.8 &#xb1; 7.1cm.H2O, P < 0.001). Moreover, bladder weight increased significantly in detrusor overactivity rats (P = 0.003, P = 0.028) and detrusor histological hypertrophy was observed. CONCLUSIONS: Ligating perineal urethra and filling cystometry with intra-urethral cannula approach is a simple and easily reproducible method to establish and evaluate the model of detrusor overactivity in rats.