The Morphological And Electrophysiological Changes Of Hippocampal Formation In Kainate-induced Chronic Temporal Lobe Epilepsy Model Rat

Objective:To establish the kainate-induced chronicity temporal lobe epilepsy(TLE) model, study the morphology and electrophysiology's changement of hippocampal formation in the model rat, discuss the mechanism of pathologic changes and epileptogenesis in this model. Methods: To make a epileptic model,kainic acid (2ug/20ul) was injected in the lateral cerebral ventricle via stereotactic technique. The confidence and feasibility were verified by ethology, EEG, pathology and fatality; then, to observe the morphology and electrophysiology's changement of hippocampal formation in the model rat: including NSE and BrdU staining to observe the changes of cell count, TUNEL staining,Timm's staining, nestin staining, and UD signals was recorded by a microelectrode amplifier. Results: The symptome of the rats could be divided clearly into three Phases: acute phase,the rats began local epilepsy immediatly after KA injection; silent period,it was a period with no symptome after acute phase; chronic phase,the spontaneous recurrent seizures were the character of this phase,and existed persistently. The typical ictal and inter-ictal epileptiform activity was record in acute and chronic phase by EEG. By cell count,the cell loss was mainly occurred in acute phase and was worst in CA3 and CA4, the neurogenesis was marked in the 8th day. The cell loss in CA1 and CA2 was not serious,and the dentate gyrus,was resistant. The apoptosis in hippocampus structure was detected by TUNEL staining. By Timm's staining,it was found that mossy fiber began sprouting in silent period and increased continuously. By nestin staining, it was found that the positive cells existed the subgranular zone(SGZ) all the life and its quantity was markedly increased in silence phase. By microelectrode amplifier, it was found that the UD'frequency of the granule...