远志对糖尿病周围神经病变大鼠坐骨神经的保护作用

Protective Effects of Polygala on Sciatic Nerve of Diabetic Peripheral Neuropathy Rats

目的探讨远志对糖尿病周围神经病变(DPN)大鼠坐骨神经的保护作用。方法雄性Wistar大鼠随机分为4组,正常对照组、DPN模型组、远志治疗组和远志预防组,每组12只。DPN模型组、远志治疗组和远志预防组大鼠均建立链脲佐菌素致糖尿病(DM)大鼠模型。待DM模型建立后,远志预防组大鼠给予远志(生药2.7g·kg-·1d-1)灌胃6周;DPN模型组和远志治疗组大鼠以尾部感觉神经传导速度(SNCV)<30m/s为标准建立DPN大鼠模型后,DPN组大鼠不再做任何处理,远志治疗组大鼠给予同等剂量远志灌胃6周。测定各组大鼠尾部SNCV,紫外分光光度法测定坐骨神经醛糖还原酶(AR)活性,免疫组织化学方法观察坐骨神经神经丝蛋白(NFP)的表达。结果与正常对照组比较,DPN模型组大鼠尾部SNCV明显降低(P<0.01),坐骨神经AR活性明显增强(P<0.01)、NFP表达明显降低(P<0.01);与DPN模型组比较,远志治疗组与远志预防组大鼠尾部SNCV明显提高(P<0.01),坐骨神经AR活性明显减弱(P<0.01)、NFP的表达明显升高(P<0.05)。结论远志可通过提高大鼠尾部SNCV、降低坐骨神经AR活性、上调坐骨神经NFP的表达,发挥对DPN大鼠坐骨神经的保护作用;且远志预处理对DM大鼠坐骨神经损伤具有预防作用。

Objective To investigate the protective effects of Polygala on sciatic nerve of diabetic peripheral neuropathy（DPN） rats.Methods Male Wistar rats were randomly divided into 4 groups（n=12）：normal control group,DPN model group,Polygala treatment group and Polygala prevention group.The rats in DPN model group,Polygala treatment group and Polygala prevention group were made diabetes model by injecting streptozocin intraperitoneally.After the diabetes model was established,the rats in Polygala prevention group were lavaged with Polygala（2.7 g·kg-1·d-1）for six weeks.The rats in DPN model group and Polygala treatment group were made DPN model when their caudal sense nerve conduction velocity（SNCV）was less than 30 m/s;then the rats in Polygala treatment group were lavaged with Polygala（2.7 g·kg-1·d-1）for six weeks.The caudal SNCV of rats in each group were respectively detected;Aldose reductase（AR）activity was detected by ultraviolet spectrophotometry and immunohistochemical staining was used to observe the expression of neurofilament protein（NFP） in sciatic nerve.Results Compared with normal rats,the caudal SNCV of DPN model rats decreased obviously,AR activity of sciatic nerve increased markedly and NFP expression decreased obviously（P〈0.01）.Compared with DPN model rats,the caudal SNCV of rats in Polygala treatment group and Polygala prevention group obviously increased,AR activity of sciatic nerve decreased markedly and NFP expression obviously（P 〈 0.01,P 〈 0.05）increased.Conclusion Polygala has protective effects on DPN rats sciatic nerve by improving caudal SNCV,decreasing AR activity and up regulating NFP expression in sciatic nerve;moreover,Polygala pretreatment has preventive effects on sciatic nerve injury of diabetes rats.