无镁液灌流大鼠海马脑片自发性癫痫样放电的药物敏感性

Drug Sensitivity of Spontaneous Epileptic Discharges in Rat Hippocampal Slices Perfused with Magnesium-free Solution

用常规海马脑片实验方法，撤除人工脑脊液中的Mg2+，0.5h内CAl区出现自发性痫样放电，1h内趋于稳定，约1／3脑片波幅可稳定2h左右，但放电频率呈缓慢增加。无Mg2+灌流后1～3h间可以观察抗病药的作用。苯受英钠（PHT）100μmol/L，氯甲酸氮卓（CBZ）100μmol/L，安定（DZP）30μmol/L，苯巴比妥钠（PB）100μmol／L，而戊酸钠（VPA）10mmol/L见及乙琥胺（ESX）10mmol/L均可抑制波幅，量效关系明显。对频率和放电时程的抑制继发于波幅抑制，且缺乏量效关系。此模型可用来筛选广谱抗病药物，具有简便易行的优点，但不适合于长时间实验观察。

When rat hippocampal slices were perfused with Mg2+-free artificial cerebrospinal fiuid, spon-taneous epileptic discharges (SED) at CAl region could be recorded within 0.5h and became stablewithin lh. Although the frequency thereafter increased gradually, the amplitude maimeined stablefor 2h in about 1/3 of slices, which allowed a 2h observation for the action of anticonvulsants.Phenytoin (PHT 100 μmol/L), carbamazepine (CBZ 100 μmol/L), diazepam (DZP 30μmol/L),sodium phenobarbital (PB 100μmol/L), sodium valproate (VPA lOmmol/L) and ethosuximide (ESXl0mmol/L) suppressed the amplitude of SED with a good concentration-response relation. The sup-pressi0n of frequency and duration of SED depended on the suppression of amplitude and lackedconcentration-response relation. The results suggest that this model is simple and easy to be used inscreening broadspectrum anticonvulasants, but is not suitable for long term observation.