Low-frequency hippocampal stimulation increases the extracellular γ-aminobutyrate level in the brain, inhibits the epileptic seizures and after discharges of the amygdala in pharmacoresistant temporal lobe epileptic rats
10.3760/cma.j.issn.1006-7876.2014.08.007
- VernacularTitle:低频海马电刺激增加耐药性颞叶癫痫大鼠脑细胞外液γ-氨基丁酸含量和抑制癫痫发作及杏仁核后放电
- Author:
Guofeng WU
;
Xiaoying LIU
;
Zhen HONG
;
Taifeng TANG
- Publication Type:Journal Article
- Keywords:
Epilepsy,temporal lobe;
Drug resistance,multiple drug;
Hippocampus;
Electric stimulation;
Extracellular fluid;
gamma-Aminobutyric acid;
Amygdala
- From:
Chinese Journal of Neurology
2014;47(8):542-547
- CountryChina
- Language:Chinese
-
Abstract:
Objective To establish a multi-drug resistant model of temporal lobe epilepsy and observe the effect of hippocampal stimulation on pharmacoresistant epileptic rats and its possible mechanism with the use of indexes including after discharges (AD) of the amygdalae,the stimulus-induced seizures and the extracellular levels of γ-aminobutyrate (GABA).Methods Totally,120 Wistar rats were used for the amygdaloid kindled model of epilepsy by chronic stimulation of amygaloid basal lateral nucleus.Based on the successful kindled model of epilepsy,we selected the pharmacoresistant and pharmacosensitive epileptic rats according to their response to phenobabital and phenytoin.We then divided the pharmacoresistant epileptic rats into the hippocampal stimulation group and control group,with 8 rats in each group.Low-frequency stimulus was conducted for two weeks in the hippocampal stimulation group.The hippocampus extracellular fluid collected by microdialysis was then used to determine the levels of GABA by a high performance liquid chromatography method after hippocampal stimulation.Results The stimulus-induced seizures were inhibited significantly,and the frequency of the AD was decreased,as well as the amplitude,compared with the control group.The extracellular level of GABA in the 8:00-9:00 am and the 8:00-9:00 pm was (32.69 ± 7.80) and (35.76 ± 6.27) μg/ml,respectively,both significantly increased as compared with the control ((26.58 ± 6.87) μg/ml,t =-21.45,P =0.000 ; (31.50 ± 4.87) μg/ml,t =-15.74,P =0.000).Conclusions The low-frequency hippocampal stimulation inhibits the seizures of the kindled model of epilepsy and decreases the frequency,the amplitude,as well as the duration of the amygdale AD in the pharmacoresistant epileptic rats,which may be contributed to the increased GABA content in extracellular fluid of the brain after stimulation.
