Objective To find out pathologieal change and the expression of neuron specific enolage (NSE)in the hippocampus dentate gyrus granular cell layer of epilepsy patients,to investigate the relationship between the pathological change and the cause of the epilepsy.Methods The specimens of hippocampus were from 9 epilepsy patients and 20 normal persons and the pathological change were investigated under the staining of the hematoxylin and eosin staining.The expression of NSE in the hippocampns denmte gyrus granular cell layer of epilepsy patients was detected by immunohistochemistry(IHC)with specific antibody,and the rate of NSE positive nenrons was evaluated.Results The nuclear pyknosis was observed in all of hippocampus from the epilepsy patients and some neurons were swelling.The positive of NSE was showed to have yellow granule;the rate of NSE positive was 28.66%.The expression of NSE of the neurons in the hippocampus dentate gyrus granular cell layer was.significantly reduced in epilepsy patients(7.9±5.6)%.The normal neuron nuclear was big and round in the middle of the cell and the nucleolus could be seen easily.The expression of NSE of the neurons in the hippocampus dentate gyrus granular cell layer was(39.0±17.4)%.Compared with normal group,the number of neurons with yellow granule was reduced.The difference of the NSE expression rate between the two group was statistically significant(t＝-5.13,P＜0.01).Conclusions The result suggests that the pathological abnormality and the reduced expression of NSE on the hippocampus dentate gyrus granular cell layer neurons could be one of the main reasons of the occurring of epilepsy.