两种不同用药途径点燃大鼠海马神经元线粒体损伤及caspase-3表达  

Mitochondriai damage and caspase-3 expression in hippocampal neurons of epileptic rats by means of different kindling

作　　者：孙建英[1] 关新华[1] 张秀清[1] 迟兆富[1] 

机构地区：[1]济南市千佛山医院保健科,250014

出　　处：《中华神经医学杂志》2007年第1期5-8,共4页Chinese Journal of Neuromedicine

基　　金：山东省自然科学基金（Y2001C10）

摘　　要：目的观察两种不同用药途径点燃大鼠海马CA3区神经元线粒体超微结构损伤及caspase-3表达。方法分别采用海人酸腹腔注射（A组）和尾静脉注射（B组）诱发大鼠癫痫持续状态（SE）。于SE终止后不同时间点取海马，电镜观察线粒体的超微结构，半定量RT-PCR和免疫组化方法分别检测caspase-3在mRNA和蛋白水平的表达，并与对照组（正常大鼠）比较。结果A组潜伏期为（97±11）min，神经元呈凋亡特征，线粒体肿胀；B组潜伏期为（48±13）min，神经元呈坏死表现，线粒体肿胀且伴膜的崩解。A组于SE后12h出现caspase-3 mRNA的表达增高（与对照组相比，P〈0．001），24h达高峰，并持续至48h；B组未检测到caspase-3 mRNA的明显增高（与对照组相比，P〉0．05）。两组动物均在SE后6h出现caspase-3蛋白水平的表达增高（P〈0．001），24h达顶峰；A组高表达持续至48h，B组在48h显著降低。结论两种不同的点燃方式导致了大鼠不同程度的线粒体损伤和caspase-3在不同水平的表达，进而决定了神经元死亡的分子机制。Objective To observe the mitochondrial ultrastructure damage and caspase-3 expression in hippocampal CA3 neurons of epileptic rats by means of different kindling. Methods Both i.p. injection of kanic acid, 12 mg/kg （Group A） and tail vein injection of kanic acid, 10 mg/kg （Group B） were employed to induce status epilepticus （SE） in rats. 3, 6, 12, 24 and 48 h after SE, the rats were killed and the hippocampus were taken out. We observed the mitochondrial ultrastructure with electron microscope, and semi-quantitative RT-PCR and immunohistochemical staining were used respectively to examine mRNA and protein level ofcaspase-3. Results The latency of Group A was （97±11） min, and ultrastructural study showed apoptotic neurons and swollen mitochondria; the latency of Group B was （48±13） min, the neurons were necrotic and the mitochondrion were seen swollen with ruptured membrane. Caspase-3 mRNA expression in Group A increased 12 h after SE（P〈0.001 vs control group）, reached the peak at 24 h, and lasted till 48 h. No increment of caspase-3 mRNA was detected in Group B（P〉0.05）. Caspase-3 protein expression of both Group A and B increased significantly 6 h after SE （P〈0.001） and reached the peak at 24 h. Besides, in Group A, caspase-3 remained high till 48 h, while in Group B, it decreased remarkably at 48 h. Conclusion The 2 different methods of kindling resulted in different degrees ofmitochondrial damage and different levels ofcaspase-3 expression, which further determined the molecular mechanisms of neuronal death.

关 键 词：癫痫持续状态 线粒体 超微结构 Caspase-3 

分 类 号：R686[医药卫生—骨科学]