摘要
目的观察海人酸(KA)致颞叶癫大鼠海马神经元线粒体损伤及c-Jun氨基末端激酶(JNK)活性的改变。方法40只雄性SD大鼠随机分为模型组(KA组)和9g/L盐水对照组(对照组)。KA组:32只,采用一侧海马注射KA(2g/kg)制备;对照组:8只,一侧海马注射等量的9g/L盐水。KA组根据点燃时间又分为6h、1d、3d和7d组,每组8只。观察其行为特征;应用电镜观察海马CA3区线粒体的超微结构;抽提海马线粒体,应用JC-1荧光染色-流式细胞仪检测法检测海马线粒体膜电位;海马线粒体琥珀酸脱氢酶(SDH)和Na+-K+-ATP酶活性检测采用SDH及ATP酶检测试剂盒测定;细胞色素C氧化酶(Cyto-Ox)检测采用Predborski法。结果1.行为学改变:大鼠注射KA后15～30min出现凝视、湿狗样抖动、头面部肌阵挛、肢体阵挛及全面强直阵挛发作,发作在二级以上,缓解后较对照组大鼠兴奋。2.海马线粒体超微结构改变:KA组在注射KA6h即可见到海马神经元线粒体超微结构损伤,出现线粒体肿胀、破裂,且随时间推移,线粒体超微结构损伤更为明显。3.海马线粒体膜电位:KA注射后6h,海马线粒体膜电位即显著下降17%,且随时间推移,线粒体膜电位下降更为显著,至7d最低,为对照组的54%。4.海马线粒体酶活性的改变:KA注射后1d,海马线粒体SDH、Cyto-Ox和Na+-K+-ATP酶活性显著下降,至7d最低,分别为对照组的51%、62%和60%。5.海马组织中JNK活性的动态变化:KA注射后6h,海马组织中JNK活性显著上调,3d达到高峰,为对照组的4.53倍。结论KA大鼠海马神经元在早期即出现线粒体损伤及JNK活性改变,提示线粒体损伤后可通过诱导JNK活化而诱导神经元凋亡。
Objective To observe the change of mitochondrial injury and c-Jun N-terminal kinase（JNK）activity in kainite acid（KA）induced epilepsy in rat.Methods KA-induced epilepsy model was induced by injection of KA into the hippocampus.Forty SD rats were randomly divided into 5 groups：control group and KA group（6 h,1 d,3 d,7 d）,8 rats in each group.The behavior was investigated.The mitochondrial ultrastructure of hippocampus CA3 area was observed with electron microscope.The mitochondrial membrane potential was detected by JC-1.The succinate dehydrogenase（SDH）,Na＋-K＋-ATPase,and cytochrome C oxidase（Cyto-Ox）activity was examined.Results 1.The behavior changes：after 15-30 min of KA injection,rats showed wet dog shakes,the clonus of the face,head and limbs,and generalized tonic-clonic convulsions.2.Mitochondrial ultrastructure changes：the mitochondrial ultrastructure damage was seen,from swelling to the rupture of membrane 6 h after KA injuction.With the development of epilepsy,the mitochondrial damage was more severe.3.Mitochondrial membrane potential：the mitochondrial membrane potential was decreased by 17% after 6 h of KA injuction.Seven days after KA injuction,the mitochondrial membrane potential was decreased by 54%.4.Mitochondrial enzyme activity：in the hippocampus,the activities of the mitochondrial SDH,Cyto-Ox,Na＋-K＋-ATPase were significantly decreased 1 d after KA injuction,and they were decreased by 51%,62% and 60%,respectively,7 d after KA injuction.5.JNK activity was dramatically increased in the time-dependent manner,it increased by 4.53-fold 3 d after KA injuction.Conclusions Mitochondrial injury-induced JNK activation may cause hippocampal cell apoptosis in KA-induced epilepsy in rat.
出处
《实用儿科临床杂志》
CAS
CSCD
北大核心
2009年第24期1885-1886,1890,共3页
Journal of Applied Clinical Pediatrics
基金
江苏省教育厅自然科学基金项目资助(08KJD310003)
南京市科技发展重大项目资助(ZKX0408)
