基于大鼠腰多裂肌损伤模型探讨电针“委中”穴对多裂肌超微结构及结蛋白表达的影响

Effect of Electro-acupuncture at“Weizhong”(BL40)on Ultra-structure and Expression of Desmin Based on Model of Lumber Multifidus Muscle Injury in Rats

目的观察电针"委中"穴对大鼠腰多裂肌损伤后超微结构及结蛋白(Desmin)表达的影响,探讨电针"委中"对多裂肌损伤后修复的部分作用机制。方法48只雄性SD大鼠,随机分为空白组、模型组、电针"委中"组,每组各16只,每组再随机分为4 d、7 d两个亚组,每组各8只。采用单次肌肉注射0.5%布比卡因盐酸盐(BPVC)建立多裂肌损伤的动物模型,电针"委中"组进行电针"委中"穴治疗,频率2/100 Hz,电流强度1~2 m A,20 min/次,1次/d,分别持续3 d、6d。空白组与模型组不进行针刺干预。造模后的第4天、第7天收集损伤多裂肌,采用透射电子显微镜观察损伤多裂肌超微结构的变化;分别采用免疫组织化学法和免疫印迹法观察不同时间点多裂肌Desmin的蛋白表达的变化。结果布比卡因注射导致多裂肌超微结构发生明显改变;免疫组织化学法和免疫印表明,与空白组比较,模型组多裂肌损伤后第4、7天Desmin的蛋白表达升高(P<0.01,P<0.01);与模型组比较,多裂肌损伤后第4天,电针"委中"组Desmin的蛋白表达升高(P<0.01),第7天,电针"委中"组Desmin的蛋白表达下降(P<0.01)。结论电针"委中"穴通过调节Desmin的蛋白表达,提前腰部多裂肌损伤修复时程的到来,促进再生肌纤维趋向成熟。

Objective To observe the intervention effect of electroacupuncture(EA)at"Weizhong"(BL40)on ultra-structure and Desmin expression in rats with Bupivacaine induced multifidus muscle injury.Methods Forty-eight male Sprague Dawley rats were randomly divided into blank group(BG),model group(MG),EA at BL40 group(WG).Each group was divided evenly into two groups(day 4,day 7)and each time point group had 8 rats.Rats in MG and WG were treated with intramuscular injection with 0.5%Bupivacaine(BPVC)at bi-multifidus muscle of lumbar 4 and 5 to establish animal model of muscle injury.Rats in WG was treated with EA at BL40(2/100 Hz in frequency,1-2 m A in intensity),20 min per treatment,once a day for 3 and 6 days respectively.Rats in BG were given no intervention.Rats in MG were treated with immobilization without EA intervention.The injured multifidus muscle was collected on the 4 th and 7 th day.The ultra-structure of multifidus muscle was observed by transmission electron microscope and the expression of Desmin of multifidus muscle was measured by immunohistochemical and Western blot.Results Bupivacaine injection can lead to significant changes in the ultra-structure of multifidus muscle.Immunohistochemical and Western blot indicated that the expression of Desmin in MG was increased(P<0.01,P<0.01)while in comparison with that in BG on the 4 th and 7 th day.The expression of Desmin was significantly increased(P<0.01)in WG on the4 th day and significantly decreased(P<0.01)on the 7 th day thanthat in MG.Conclusion Electroacupuncture at"Weizhong"(BL40)can advance the regeneration process of injured multifidus muscle and promote the maturation of regenerated muscle through the cytoskeletal protein Desmin.