模拟分娩损伤及绝经对压力性尿失禁模型大鼠尿道周围结缔组织转化生长因子β1和弹性蛋白表达的影响

Impact of Analog Birth Injuries and Post-menopausal on the Expression of TGF-beta1 and Elastin in Periurethral Connective Tissue of Stress Urinary Incontinence Rat Models

目的:探讨模拟分娩损伤及绝经对压力性尿失禁(SUI)模型大鼠尿道周围结缔组织转化生长因子β1(TGFβ1)和弹性蛋白(elastin)表达的影响。方法:51只雌性SD大鼠随机分为3组:阴性对照组(正常未孕大鼠)、阳性对照组(分娩组)、SUI组(分娩、模拟产伤、卵巢去势),造模前和处死前均行尿道动力学检测,于术后4周处死大鼠,收集大鼠尿道周围结缔组织进行常规石蜡切片、HE染色、弹性纤维特殊染色,免疫荧光实验和Western blotting方法检测各组尿道周围结缔组织TGFβ1和弹性蛋白的蛋白表达情况。结果:SUI组最大膀胱容量和漏尿点压力明显较阳性对照组和阴性对照组下降(P均<0.01)。弹性纤维特殊染色显示阴性对照组和阳性对照组弹性纤维完整致密,SUI组弹性纤维较对照组减少、稀疏、变细(P均<0.01)。Western blotting检测结果显示阴性对照组和阳性对照组尿道周围结缔组织均见TGFβ1和弹性蛋白的高表达,2个对照组间比较差异均无统计学意义(P均>0.05)。SUI组在造模后4周TGFβ1和弹性蛋白的表达均较对照组明显下降(P均<0.01)。结论:尿道周围结缔组织弹性纤维的破坏和缺失可能与SUI的发生关系密切,弹性蛋白和TGFβ1的减少可能共同参与了SUI的发生、发展。

Objective： To investigate the impact of analog birth injuries and post-menopausal on the TGF- betal （TGF-β1） and elastin expression in urethral connective tissue of stress urinary incontinence （SUI） rat models. Methods： Totally 51 female SD rats were randomly divided into three groups： negative control group （normal nonpregnant rats）, positive control group （delivery group） and SUI model group （childbirth, analog birth trauma, ovariectomized）. Urethra dynamics detection was done before the SUI model was made and the rats were sacrificed. The rats were sacrificed 4 weeks after the surgery. The rat periurethral connective tissue was made into paraffin section. HE staining, special staining of elastic fibers, immunofluorescence assay and Western blotting were used to detect the protein expression of TGF-β1 and elastin. Results： SUI group＇s max bladder capacity and leak point pressure were significantly lower than those in the positive control group and the negative control group （P〈0.01）. Special staining of elastic fibers of the two control groups were complete and dense, while SUI group＇s were few and sparse （P〈0.01）. Western blotting test results showed that both in the negative control group and the positive control group, TGF-β1 and elastin showed high expression in the periurethral connective tissue. Between the two control groups, the difference was not statistically significant （P〉0.05）. Four weeks after modeling, SUI group＇s TGF-β1 and elastin expression was decreased significantly compared with the control （P〈0.01）. Conclusion： Destruction of elastic fibers of the connective tissue around the urethra and deletions may be closely related to the occurrence of SUI. Declines in elastin and TGF-β1 levels may be jointly involved in the occurrence and development of SUI.