Stress urinary incontinence following vaginal trauma involves remodeling of urethral connective tissue in female mice

Objective

The molecular mechanisms underlying stress urinary incontinence (SUI) are not clear. This study was conducted to evaluate molecular alterations in the urethras of mice with experimentally induced SUI.

Study design

Eighteen virgin female mice were equally distributed into three groups as follows: two groups undergoing vaginal distension (VD) for 1 h with 3 mm and 8 mm dilators each, and a non-instrumented control group. Changes in leak point pressure (LPP), morphology, lysyl oxidase (LOX) expression and the metabolism of urethral connective tissue were assessed.

Results

The LPP was significantly decreased in the 3 mm and 8 mm VD groups compared with that in the control group. Collagen and elastin expression in the urethra was significantly decreased in the 8 mm VD group compared with that in the control group, while LOX expression was significantly enhanced.

Conclusions

SUI following vaginal trauma involves over-expression of LOX and decreased synthesis of extracellular matrix components or increased proteolysis in the urethra.