摘要：
目的 研究苦参素对实验性自身免疫性脑脊髓炎(EAE)大鼠钙蛋白酶(Calpain)和微管相关蛋白2(MAP-2)表达的影响.方法 采用随机数字表法将60只大鼠分为正常对照组、模型组、地塞米松组(1 mg/kg)、苦参素高剂量组(250 mg/kg)、苦参素中剂量组(200 mg/kg)及苦参素低剂量组(150 mg/kg).除正常对照组外,其他各组大鼠接受豚鼠全脊髓匀浆及完全弗氏佐剂制成的抗原乳剂干预并制备EAE模型.地塞米松组及苦参素高、中、低剂量组大鼠连续药物干预16 d,记录大鼠发病症状,观察脊髓病理改变,半定量聚合酶链反应(RT-PCR)法测定脊髓中 μ-钙蛋白酶(μ-Calpain)和m-钙蛋白酶(m-Calpain)含量的变化,免疫组织化学法检测脊髓中MAP-2的表达.结果 苦参素高、中、低剂量组大鼠神经功能评分分别为(1.28±0.59)分、(1.45±0.64)分、(2.09±0.71)分,较模型组的(2.85±0.78)分显著降低(t=5.345、4.314、2.869,均P<0.05).与模型组[(2.49±0.29)分]相比,苦参素高剂量组[(1.04±0.26)分]、苦参素中剂量组[(1.29±0.20)分]、苦参素低剂量组[(1.77±0.24)分]HE评分均显著降低,差异均有统计学意义(t=5.185、4.274、3.629,均P<0.01).苦参素高、中、低剂量组 μ-Calpain mRNA含量均低于模型组(t=10.656、9.418、7.044,均P<0.01);m-Calpain mRNA含量均低于模型组(t=6.332、5.416、3.978,均P<0.01);MAP-2蛋白含量均高于模型组(t=12.841、9.924、7.038,均P<0.01).结论 苦参素可能通过抑制EAE大鼠Calpain过度表达、上调MAP-2水平,发挥对EAE大鼠的保护作用.%Objective To study the effect of matrine on Calpain and MAP-2 in rats with experimental autoimmune encephalomyelitis(EAE).Methods In accordance with the random number table ,60 Wistar rats were divided into 6 groups randomly: normal group,model group,dexamethasone(DEX)-treated group(1mg/kg),high-dose matrine(MAT)-treated group(250mg/kg),middle-dose MAT-treated group(200mg/kg) and low-dose MAT-treated group(150mg/kg).The EAE models were induced by immunized spinal cord extracts of guinea pig with complete Freunds'adjuvant.Rats of three MAT-treated groups and DEX-treated group were injected intraper-itoneally with MAT and DEX daily for 16 days respectively,whereas rats of normal group and model group were injected intraperitoneally with normal saline.Clinical signs of rats in six groups were observed daily .Hematoxylin-eosin (HE) was used to analyze histopathological evaluation of spinal cord .μ-Calpain,m-Calpain and MAP-2 in spinal cord were determined using RT-PCR and immunohistochemistry respectively .Results Compared with the model group[(2.85 ±0.78)points],the clinical scores were significantly decreased in high-dose-MAT group[(1.28 ± 0.59) points], middle-dose-MAT group [(1.45 ±0.64) points] and low-dose-MAT group [(2.09 ± 0.71)points](t =5.345,4.314,2.869,all P <0.05).The HE score of rats in model group[(2.49 ±0.29)points] was significantly higher than that in high-dose-MAT group[(1.04 ±0.26) points],middle-dose-MAT group [(1.29 ±0.20) points] and low-dose-MAT group[(1.77 ±0.24)points] (t =5.185,4.274,3.629,all P <0.01).The levels of μ-Calpain mRNA and m-Calpain mRNA in the three MAT-treated groups were significantly lower than those in model group(t =10.656,9.418,7.044,all P <0.01;t =6.332,5.416,3.978,all P <0.01).In addition,the expression of MAP-2 in the spinal cord of EAE rats showed a marked elevation after MAT treatment (t =12.841,9.924,7.038,all P <0.01).Conclusion Matrine may be an effective therapeutic approach for EAE by inhibiting Calpain and increase MAP-2 expression.
