戊四氮点燃癫癎大鼠海马5-羟色胺能神经递质的动态研究

Rats Hippocampus 5-HT-energic Variance in PTZ-induced Kindling Epilepsy

目的:观察戊四氮(PTZ)点燃癫癎形成过程中大鼠海马5-羟色胺(5-HT)能神经递质的变化。方法:用PTZ制作癫癎大鼠模型,将造模成功大鼠分为戊四氮急性发作组(PTZ 1组)和戊四氮慢性点燃组(PTZ 2组),同时设立对照组(腹腔注射生理盐水)。在体微透析取样,观察大鼠行为、脑电图(EEG)和海马5-HT能神经递质的变化。结果:PTZ 1组癫癎发作时EEG自发放电逐级加重;癫癎发作时海马5-HT水平与对照组、发作前和发作后比较显著升高(P<0.05);海马5-羟吲哚乙酸(5-HIAA)水平差异无统计学意义;5-HT转化率(5-HIAA/5-HT)降低,差异有统计学意义(P<0.05)。PTZ 2组点燃后大鼠出现自发癫癎发作,EEG在发作间期出现自发放电;5-HT和5-HIAA水平在点燃期、维持点燃期、对照组间比较差异有统计学意义(P<0.05)。结论:大鼠癫癎发作时海马5-HT水平显著升高,发作后恢复正常;在癫癎形成过程中,早期5-HT水平一过性升高、PTZ点燃后和发作间期海马5-HT水平逐渐降低。

Aim：To investigate the variance of 5-HT energic neurotransmitter in pentylenetrazol induced kindling epilepsy rats hippocampus.Methods：Epilepsy rat models were made by PTZ,and the rats were divided into PTZ acute group（PTZ 1 group） and PTZ-induced kindling group（PTZ 2 group）,the control group was set up at the same time.Microdialysis was done in vivo.The rats＇ behavior,their EEG and the changes of hippocampus 5-HT were observed.Results：In PTZ 1 group,EEG showed gradually aggravated epileptic discharge with time and the concentrations of 5-HT in hippocampus were increased significantly compared with that of the control group,that at the time before and after seizure（P0.05）.There were not significant statistic difference in the concentrations of 5-HIAA.5-HT turnover（5-HIAA/5-HT） decreased with significant statistic difference.In PTZ 2 group,spontaneous discharge appeared in interictal.During the kindling period, the concentrations of 5-HT and 5-HIAA in hippocampus increased.In advanced stage of kindling,their concentrations decreased significantly compared with the control（P0.05）.Conclusion：PTZ-induced seizures result in significant increase of hippocampus 5-HT levels,and 5-HT levels decrease to normal after seizures.During epilepsy development,5-HT levels have an transient increase in early stage of kindling.5-HT decrease gradually into normal levels after rats being kindled and in interictal.