阴部神经电刺激在阴部神经挤压伤诱导的雌性压力性尿失禁大鼠模型中的作用研究

The role of pudendal nerve electrical stimulation in female stress urinary incontinence rat model induced by pudendal nerve crush

目的探讨阴部神经电刺激(perineal nerve electrical stimulation,PNES)对压力性尿失禁(stress urinary incontinence,SUI)大鼠模型盆底功能和阴部神经修复的作用。方法60只SD雌性大鼠随机分为4组,对照组(CON组)、假手术组(Sham组)、损伤组(PNC组)及治疗组(PNC+ES组),各组大鼠均在处理后7 d进行喷嚏试验与尿流动力学检测,包括最大膀胱容量(maximum bladder capacity,MBC)和漏尿点压力(leak point pressure,LPP),随后取阴部神经组织及尿道膀胱颈周围组织标本,使用Masson三色染色观察尿周组织肌肉及胶原的变化,使用HE染色观察阴部神经损伤及修复状况。结果与CON组比较,Sham组喷嚏试验阳性率、MBC值和LPP值差异均无统计学意义(P>0.05),其阴部神经纤维均排列整齐,走形正常,膀胱颈尿道交界部组织结构完整,均无异常改变;PNC组大鼠MBC值与LPP值明显降低(P<0.001),喷嚏试验阳性率明显增加(P<0.001),阴部神经存在明显的神经缺损与离断现象,膀胱颈尿道交界部肌纤维含量明显减少(P<0.001),胶原纤维含量降低(P<0.05)。与PNC组相比,经过PNES治疗后,大鼠MBC值和LPP值明显回升(P<0.001),喷嚏试验阳性率下降(P<0.05),阴部神经可见修复痕迹,神经组织大部分愈合,膀胱颈尿道交界部肌纤维含量与胶原纤维含量均明显上升(P<0.05)。结论PNES能显著改善阴部神经挤压伤造模SUI大鼠的尿动力功能,修复损伤后的阴部神经及尿周组织。

Objective To investigate the effect of perineal nerve electrical stimulation(PNES)on pelvic floor function and perineal nerve repairment in rats model of stress urinary incontinence(SUI).Methods 60 SD female rats were randomly divided into 4 groups:control group(CON group),sham operation group(Sham group),injury group(PNC group)and treatment group(PNC+ES group).After 7 days of modeling,sneeze test and urodynamic examination including maximum bladder capacity(MBC)and leak point pressure(LPP)were performed to evaluate the effect of PNES on SUI.The pudendal nerve tissue and the tissue around the bladder neck of the urethra were taken to detect the changes in tissue levels.The changes of muscles and collagens were observed by Masson staining.The pudendal nerve injury and repairment were observed by HE staining.Results Compared with CON group,there were no significant differences in the positive rate of sneeze test,MBC value and LPP value in the Sham group(P>0.05).The nerve fibers of the pudendal region were arranged neatly,the shape was normal,and the tissue structure of the bladder neck and urethra junction was complete,and there was no abnormal change.Meanwhile,compared with the CON group,the MBC value and LPP value of the PNC group were significantly lower(P<0.001),and the positive rate of sneeze test was significantly higher(P<0.001).The pudendal nerves were arranged sparsely and the nerves were in disorder,the content of muscle fiber(P<0.001)and collagen fiber around the urethra(P<0.05)decreased significantly.Compared with PNC group,the MBC and LPP values increased significantly(P<0.001)and the positive rate of sneeze test decreased(P<0.05)after PNES.The pudendal nerve showed obvious nerve repair marks,most of the nerve tissue healed,and the content of muscle fiber and collagen fiber around the urethra increased significantly(P<0.05).Conclusion PNES can significantly improve the urodynamic function of SUI rats model induced by pudendal nerve crush,and repair the injured pudendal nerve and periurethral tissue.