亲环蛋白D在癫痫大鼠模型海马组织中的表达及意义

Expression of cyclophilin D in hippocampus tissue of epilepsy rats and its significance

目的探讨亲环蛋白D(CypD)在癫痫大鼠模型海马组织中的表达及意义。方法用氯化锂-匹罗卡品腹腔注射40只6～8周龄的SD大鼠建立癫痫模型,最终取20只癫痫发作级别达Ⅳ级以上的大鼠纳入实验。将癫痫发作的SD大鼠按照随机数字表法分为癫痫组和CypD抑制剂环孢素A(CsA)处理组(Cs A组),每组10只,另取10只SD大鼠作为对照组。CsA组大鼠腹腔注射6mg/kg CsA,癫痫组和对照组腹腔注射等体积0.9%氯化钠注射液。采用PCR检测CypD mRNA相对表达量。采用Western blot检测Cyp D、Caspase-3、细胞色素C(Cyt-C)相对表达量。采用TUNEL染色法检测海马组织细胞凋亡数,采用WST-1法检测超氧化物歧化酶(SOD)、钼酸铵法检测过氧化氢酶(CAT)、TBA法检测丙二醛(MDA)含量。结果与对照组比较,癫痫组CypD mRNA与蛋白相对表达量,海马组织细胞凋亡数和Cyt-C、Caspase-3相对表达量、MDA含量均较高,SOD、CAT含量降低,差异均有统计学意义(P<0.05)。与癫痫组比较,Cs A组CypD蛋白、mRNA相对表达量、海马组织细胞凋亡数、Cyt-C、Caspase-3相对表达量、MDA含量降低(P<0.05);SOD、CAT含量明显增高,差异均有统计学意义(P<0.05)。结论 CypD在氯化锂-匹罗卡品诱发的癫痫大鼠海马组织中表达量增加,具有促进海马组织线粒体凋亡途径启动的作用。

Objective To investigate the expression and role of cyclophilin D(CypD) in hippocampus tissue of epilepsy rats.Methods Epilepsy was induced by intraperitoneal injection of lithium-pilocarpine in 40 Sprague-Dwaley(SD) rats. Twenty SD rats with grade Ⅳ epilepsy seizures were were randomly divided into 2 groups: Cs A group(treated with cyclosporin A, n=10) and epilepsy group(no treatment, n=10). In addition, 10 healthy SD served as the control group. Rats in Cs A group were intraperitoneally injected with 6 mg/kg Cs A,while the control group was intraperitoneally injected with equal amount of saline. The CypD m RNA was detected by PCR. The relative expression of CypD, Caspase-3, cytochrome C(Cyt-C) were detected by Western blot. TUNEL was used to detected the number of apoptotic cells in the hippocampus. The content of superoxide dismutase(SOD), catalase(CAT) and malondialdehyde(MDA) in hippocampus were detected by WST-1 method, ammonium molybdate method and TBA method, respectively. Results Compared with control group, the relative expression of CypD protein and m RNA in epilepsy group increased significantly(P <0.05), the number of apoptotic cells in hippocampus and the relative expression of Cyt-C and Caspase-3 increased(P <0.05), the content of SOD and CAT decreased, while the content of MDA increased significantly(both P<0.05). Compared with epilepsy group, the relative expression of CypD protein and m RNA in Cs A group was significantly lower(P <0.05). The number of apoptotic cells and the relative expression of Cyt-C and Caspase-3 were significantly lower(P<0.05), the content of SOD and CAT were higher, while the content of MDA was lower(both P<0.05). Conclusion The expression of CypD increased and it may be involved in mitochondrial apoptosis in hippocampus tissue of epilepsy rats.