齿状回在慢性电刺激诱发大鼠颞叶癫痫中的可能作用  

Possible role of dentate gyrus in greneration of rat temporal lobe epilepsy induced by electrical stimulation

作　　者：张先荣[1] 韩丹[1] 唐岳枫[2] 刘买利[2] 尹世金[1] 

机构地区：[1]武汉大学医院生理学教研室,武汉430071 [2]中国科学院武汉物理与数学研究所波谱与原子分子物理国家重点实验室,武汉430071

出　　处：《生理学报》2001年第3期235-239,共5页Acta Physiologica Sinica

基　　金：This work was ,supported by the National Natural Science Foundation of China(No.29925515) and the Natural Science Foundation of

摘　　要：本文探讨了齿的状回（ＤＧ）及海马（ＨＰＣ）在颞叶癫痫发生中的可能作用。分别强直电刺激（６０Ｈｚ，０．４～０．６ｍＡ，２ｓ）大鼠右背侧海马（ＤＨＰＣ）和 ＤＧ制作慢性癫痫模型，观察大鼠行为、深部电图及脑区Ｔ２加权核磁共振成像（Ｔ２－ＷＩ）的改变。发现ＤＧ刺激组大鼠的原发性湿狗抖频率明显低于ＨＰＣ刺激组（Ｐ＜０．０５）；其深部电图脑波的下均最高振幅也明显低于ＨＰＣ刺激组大鼠（Ｐ＜０．０５），而ＨＰＣ电图的电振荡发生率增加。另外，ＨＰＣ刺激组大鼠呈现Ｔ２－ＷＩ高信号强度，而ＤＧ刺激组大鼠Ｔ２－ＷＩ信号强度无明显改变（Ｐ＜０．０５）。结果表明，ＤＧ在内嗅皮质（ＥＣ）－ＨＰＣ环路中可能起着某种“过滤器”的作用，限制来自于大脑皮层通过ＥＣ到达ＨＰＣ的神经信息，一旦丧失该作用可以导致ＨＰＣ的损害并发生颞叶癫痫。Possible role of the dentate gyrus (DG) and the hippocampus (HPC) in temporal lobe epileptogensis was investigated in an electrogertic model of rat epilepsy. Chronic tetani (60 Hz, 0.4-0.6 mA, 2 s) were administered once daily for 7 days to the right dorsal hippocampus (DHPC) or the right DG. Animal behavior was observed and depth electro-graphic seizures and T2-weight- ed magnetic resonance images (T2- WI) were measured. Results indicated that the frequency of primary wet dog shakes (WEDS) in the DG-stimulated rats was much lower than that in the DHPC-stimulated rats (P < 0.05). The mean maximal wave-amplitude in DG electrographs was also much lower than that in HPC electrographs (P < 0.05). The oscillations proportion of DHPC elcctro-graphs increased after DHPC-tetanization (from 2/9 up to 7/9 rats). T2-WI hyperintensity in the lateral ventricle area was detected only in the DHPC-tetanized rats, not in the DG-tetanized rats (P <0.05). These results suggest that the DG acts as a filtering site in the entorhinal cortex-HPC neuronal circuitry and its dysfunction causes damage to the HPC and the generation of temporal lobe epilepsy.

关 键 词：海马 齿状回 癫痫 T2加权核磁共振成像 

分 类 号：R742.1[医药卫生—神经病学与精神病学]