Comparison and analysis of three types of stress urinary incontinence mice models

Abstract

Objective To compare the 3 kinds of stress urinary incontinence (SUI) mice models. Methods 140 female mice were randomly divided into 4 groups: control group, vaginal distension (VD) group, ovariectomy (OV) group, and VD+ OV group. There were 65 mice in control group, and 25 mice each in the rest three groups. The postoperative infection rate and mortality rate were recorded, and maximum bladder capacity (MBC) and leak point pressures (LPPs) were measured. The contents and activity of matrix metalloproteinase (MMP)-2 and MMP-9 were detected by zymography assay after surgery. The advantages and disadvantages of the three models were comparatively analyzed. Results The MBC/abdominal leak point pressure (ALPP)/bladder leak point pressure (BLPP) in control group, VD group, OV group, and VD+ OV group were respectively (0.101±0.014) ml/(46.420±6.399) cmH2O/(44.180±4.912) cmH2O (1 cmH2O=0.098 kPa); (0.081±0.015) ml/(30.990±5.021) cmH2O /(26.680±6.485) cmH2O; (0.095±0.010) ml/(44.330±6.465) cmH2O /(41.450±6.474) cmH2O and (0.071±0.013) ml/(28.920±5.232) cmH2O /(22.120±7.412) cmH2O, reduced significantly in VD group (P value respectively were 0.000, 0.000 and 0.000) and VD+ OV group (P value respectively were 0.000, 0.000 and 0.000), compared with control group and OV group, but the difference between VD+ OV group and VD group was not notable (P value respectively were 0.051, 0.245 and 0.062), or between OV group and control group (P value respectively were 0.093, 0.238 and 0.064); The expression of MMP-2/MMP-9 in these group were respectively 13.930±0.823/9.610±0.771, 14.990±0.908/11.100±0.735, 13.890±0.707/9.761±0.680, 15.470±1.070/11.240±0.750, increased notably in VD group (P value respectively were 0.003/0.000 and 0.001/0.000) and VD+ OV group (P value respectively were 0.000/0.000 and 0.000/0.000) compared with control grou, but the difference of MMP-2/MMP-9 between the VD+ OV group and VD group was not significant (P value respectively were 0.216/0.604), or between OV group and control group (P value respectively were 0.912/0.573). Conclusion Vaginal distension and vaginal distension with ovariectomy can both establish SUI mice models, but vaginal distension is preferable. Key words: Stress Urinary Incontinence; Vaginal Distension; Ovariectomy; Urine Dynamics Measurement