Ⅰ型大麻素受体对脊髓损伤小鼠和小胶质细胞活化的影响

Protective Effect and Mechanism of Cannabinoid 1 Receptor on and Microglia Activation in Mice with Spinal Cord Injury

目的:探讨Ⅰ型大麻素受体(CB1R)对脊髓损伤小鼠和小胶质细胞活化的影响。方法:36只SPF级C57BL/6雌性小鼠,随机分为对照组、模型组和药物组,通过改良Allen's法,构建小鼠脊髓损伤模型。分别于术后第1天、第7天和第14天,进行行为学评价。术后第14天处死小鼠,Western blotting法检测脊髓组织髓鞘碱性蛋白(MBP)、脑源性神经营养因子(BDNF)和神经生长因子(NGF)蛋白表达。酶联免疫吸附法测定小鼠血清IL-6、IL-17和TNF-α含量。免疫荧光双染检测脊髓组织钙离子结合调节因子(IBA)-1和ED-1阳性细胞表达。结果:与对照组比较,模型组小鼠术后BMS评分和斜板倾斜度明显降低,血清IL-6、IL-17和TNF-α含量、脊髓组织MBP、BNDF和NGF蛋白含量及IBA1/ED1双阳性细胞均明显升高(P<0.05);与模型组比较,药物组小鼠术后BMS评分、斜板倾斜度、脊髓组织MBP、BNDF和NGF蛋白含量均明显升高,血清IL-6、IL-17和TNF-α含量以及脊髓组织IBA1/ED1双阳性细胞均明显降低(P<0.05)。结论:CB1R通过抑制小胶质细胞活化和炎症反应,降低脊髓损伤。

Objective:To investigate the protective effect and mechanism of cannabinoid 1 receptor(CB1R)on and microglia activation in mice with spinal cord injury.Methods:Thirty-six female C57BL/6 mice were randomly divided into control group,model group and drug group.The mouse spinal cord injury model was constructed by modified Allen's method.The behavioral evaluation was performed on the 1th,7th,and 14th day after the operation,respectively.Western blotting was used to detect the protein expression of myelin basic protein(MBP),brain-derived neurotrophic factor(BDNF)and nerve growth factor(NGF)in spinal cord tissue.Enzyme-linked immunosorbent assay was used to determine the serum levels of IL-6,IL-17 and TNF-αin mice.Immunofluorescence double staining was used to detect the expression of calcium ion binding regulator(IBA)-1 and ED-1 positive cells in spinal cord tissue.Results:Compared with the control group,the BMS score and the inclination of the oblique plate in the model group were significantly reduced,the serum levels of IL-6,IL-17 and TNF-α,the protein expression of MBP,BNDF and NGF and the number of IBA-1/ED-1 positive activated microglia in the model group was significantly increased(P<0.05).Compared with the model group,the BMS score,the inclination of the oblique plate and the protein expression of MBP,BNDF and NGF in the drug group were significantly increased,the serum levels of IL-6,IL-17 and TNF-αand the number of IBA-1/ED-1 positive activated microglia(P<0.05).Conclusion:CB1R reduces spinal cord injury by inhibiting microglia activation and inflammation.