THE ROLE OF ASTROCYTES ACTIVATED BY TNF? IN THE RELAPSE OF CHRONIC EPILEPSY / 解剖学报

ABSTRACT

Objective To investigate the effect of astrocytes activated by TNF? on the relapse of epilepsy. Methods The purified astrocytes of cultured rat hippocampus were stimulated by TNF?.The expression of NF\|? Bp65 was checked by immunocytochemical method and the release of glutamate(Glu) from astrocytes was measured by high performance liquid chromatography(HPLC).The astrocytes conditioned medium(ACM) stimulated by TNF? was collected and injected into lateral ventricle of chronic Coriaria Lactone kindled rats during the interictal period.The changes both in behavior and electroencephalogram(EEG) were recorded.The expression of NF\|? Bp65 and glial fibrillary acidic protein(GFAP) of hippocampus were also studied by immunocytochemical method. Results 1.TNF? could promote the release of Glu by astrocytes and quickly induce the nuclear expression of NF\|? Bp65 in cultured astrocytes.2.After lateral ventricular injection,four class epileptic behaviors were induced,which were confirmed by epileptic charge EEG.At 0^5?h after injection of ACM,NF ? Bp65 expression in hippocampal cells especially in the CAl area were induced.It reached to the maximal levels at 2\|4?h and returned to control level at 8h.At 1h after injection of ACM,the increase of the number of positive GFAP \|immunoreactivity(IR) cells of hippocampus could be observed.The expression of GFAP reached to the top level at 4h and still maintained at a higher level than the control group until 8h.Conclusion\ Astrocytes activa\|ted by TNF? could induce the relapse of epilepsy by some solube neuro\|active substance.