电针对骶上脊髓损伤后神经源性膀胱尿流动力学及逼尿肌垂体腺苷酸环化酶激活肽/环磷酸腺苷/蛋白激酶A信号通路的影响

Effect of electroacupuncture on urodynamics of neurogenic bladder and PACAP/cAMP/PKA signaling pathway in detrusor tissue of rats after suprasacral spinal cord injury

目的:观察电针对骶上脊髓损伤后神经源性膀胱尿流动力学及逼尿肌组织中垂体腺苷酸环化酶激活肽(PACAP)/环磷酸腺苷(cAMP)/蛋白激酶A(PKA)信号通路的影响,探讨电针改善骶上脊髓损伤休克期后逼尿肌反射亢进型膀胱功能的可能机制。方法:60只雌性SD大鼠按随机数字表法分为空白组12只、假手术组12只、造模组36只。造模组采用改良胸(T)10脊髓横断法制作神经源性膀胱模型。将造模成功的大鼠随机分为模型组12只、电针治疗组12只。电针治疗组造模后第19天于"次髎""中极""三阴交"给予电针干预,20 min/次,1次/d,连续治疗7 d。干预结束后各组行尿流动力学检测,HE染色法观察膀胱逼尿肌组织病理形态学变化,免疫组织化学法检测逼尿肌PACAP38的表达,Western blot法检测逼尿肌PACAP38蛋白的相对表达量,PCR法测定PACAP mRNA表达,ELISA法测定逼尿肌cAMP、PKA含量。结果:与空白组和假手术组比较,模型组大鼠膀胱最大容量及膀胱顺应性均显著降低(P<0.01),膀胱基础压力和漏尿点压力显著升高(P<0.01);膀胱逼尿肌PACAP38阳性表达、蛋白及mRNA表达水平明显降低(P<0.01,P<0.05), cAMP、PKA含量显著降低(P<0.01)。与模型组比较,电针治疗组大鼠膀胱最大容量及膀胱顺应性明显升高(P<0.01);膀胱基础压力和漏尿点压力降低(P<0.05);膀胱逼尿肌PACAP38阳性表达、蛋白及mRNA表达水平明显升高(P<0.01,P<0.05),cAMP、PKA含量显著升高(P<0.05)。结论:电针"次髎""中极""三阴交"可改善脊髓损伤后神经源性膀胱大鼠膀胱功能,其机制可能与电针上调膀胱逼尿肌中PACAP38、cAMP、PKA表达,激活PACAP/cAMP/PKA信号通路,从而促进逼尿肌舒张有关。

Objective To observe the effect of electroacupuncture(EA)on urodynamics of neurogenic bladder and pituitary adenylate cyclase activating peptide(PACAP)/cyclic adenosine monophosphate(cAMP)/protein kinase A(PKA)signaling pathway in detrusor tissue of rats after suprasacral spinal cord injury(SCI),so as to explore its possible mechanism in improving detrusor hyperreflexia bladder function after shock stage of suprasacral SCI.Methods Female SD rats were randomly divided into control,sham operation,model and EA groups,with 12 rats in each group.T10 spinal cord transection(SCT)was performed by surgery.Rats in the EA group were given EA(10 Hz/50 Hz,20 min)at"Ciliao"(BL32),"Zhongji"(CV3)and"Sanyinjiao"(SP6)once daily for 7 days.After the intervention,urodynamics testing was detected in each group.HE staining was used to observe the morphological changes of bladder detrusor.The protein and mRNA expression of PACAP38 in detrusor was detected by immunohistochemistry,Western blot and real-time quantitive PCR,respectively.The contents of cAMP and PKA were determined by ELISA.Results Compared with the control and sham operation groups,the maximum bladder capacity and bladder com-pliance,and the protein and mRNA expression of PACAP38,and the contents of cAMP and PKA of the model group were significantly decreased(P<0.01,P<0.05),while the base pressure and leakage point pressure of bladder were significantly increased(P<0.01).After EA intervention,the above indexes were all reversed in the EA group relevant to those of the model group(P<0.01,P<0.05).Conclusion EA at BL32,CV3 and SP6 can improve the bladder function in rats with bladder detrusor hyperreflexia after SCI,which may be related to its effect in activating the PACAP/cAMP/PKA signaling pathway in detrusor tissue.