戊四氮致猫急性癫发作相关脑区锰离子增强功能MRI成像的研究

Study on image of Mn^(2+)-fMRI on encephalic region correlated with the acute epileptic seizure of cat induced by pentylenetetrazol

目的探讨锰离子(Mn2+)增强功能MRI成像对确定癫发作相关脑区的价值。并进一步确定癫与钙超载的相关性,从而对癫的发病机制和定位进行研究。方法给成年猫肌肉注射戊四氮(PTZ)制作癫疒间模型,观察猫的行为学和脑电图改变;在癫疒间急性发作时和发作后24h进行Mn2+功能MRI成像检查;对信号明显增强的脑区做病理学检查并与对照组比较。结果PTZ致疒间猫脑电图呈阵发性高波幅棘-慢波。癫发作组猫Mn2+功能MRI成像显示大脑皮质明显弥漫性增强,其中额、顶、枕叶脑皮质增强率达34.6%,颞叶皮质增强率达约22.9%,与对照组相比差异有极显著性(均P<0.01)。癫疒间发作后24h组Mn2+功能MRI成像仍显示额、顶叶明显强化。强化区的神经元有明显变性、坏死。结论额、顶叶为PTZ致疒间猫癫疒间发作形成的相关脑区,Mn2+增强功能MRI成像能显示癫疒间发作的部位,并可进一步揭示癫疒间发病机制。

Objective To determine the value of locate the eneephalie region eorrelated with epilepsy by Mn^2＋ - fMRI and further to determine the correlation of epilepsy and calcium overloading. Accordingly, the study was carried out on the pathogenesy and allocation. Methods The adult eats were made to epileptic models by intramuscular injected with pontylenetetrazol （PTZ）, the behavioral and EEG ehanges were observed, and the Mn^2＋ -fMRI was done at the time of acute epileptic seizure and at the time of 24 hours after the epileptic seizure; the pathological examination was made on signal enhanced eneephalie regions compared with the control group. Results The EEG of the epileptie eats by PTZ showed paroxysmal spine-slow waves with high amplitude. The Mn^2＋ -fMRI of epileptie seizure group showed eerebral eortex diffuse signal enhaneement, the enhaneement rate of frontal-parietal-oeeipital lobe was 34.6% ,the enhaneement rate of temporal lobe was 22.9% , and they had signifieant differenees with the eontrol group（ all P 〈 0. 01 ）. The Mn^2＋ -fMRI at the time of 24 hours after seizure also showed signal enhancement on frontal-parietal lobe. The neurons of enhaneed eneephalie regions showed obvious degeneration and necrosis. Conclusion Frontal parietal lobe is the eorrelated eneephalie regions of epilepy. Mn^2＋ -fMRI earl play an important role in allocation and revealing pathogenesy of epileptie seizures.