Study Of The Relationship Between Glutamate Acid Transporter And C-FOS Gene In The Astrocyte And Epilepsy

Part â… : Study of the change of glutamate acid transporter in hippocampus of rat brains following kainic acid induced seizure activity Objective: to study the change of glutamate acid transporter GLAST and GLT-1 in hippocampus of rat brains following kainic acid induced seizure activity, and explore relationship between astrocyte and seizure susceptibility. Methods: A model of rat brains following kainic acid induced seizure activity was eatablished. Hippocampus of rat brains was sampled for analysis 6h,12h,24h,48h and 7d after seizure activity. GLAST mRNA and GLT-1 mRNA was determined by the reverse-transcription PCR. Semiquantiative analysis of RT-PCR products was done with an eletronic U.V. transillu minator. Microscopical changes of GLAST mRNA and GLT-1 mRNA was observed. Results: The GLAST mRNA of ground of Epilepsy significantly decreased at 12h,24h and 48h after seizure activity, and returned to level of control ground at 7d. The GLT-1 mRNA of ground of Epilepsy appeared the trend of decrease at 7d after seizure activity. Conclusion: The expression of the glutamate acid transporter GLASTmRNA and GLT-1mRNA in hippocampus had a downregulation after seizure activity which make astrocyte ability of transporting glutamate acid decrease and glutamate acid in gap of synapses increase, and this change would allow seizure susceptibility increase .It indicates that astrocyte could be related to the development of seizure susceptibility.Part â…¡: C-FOS gene expression of hippocampal astrocytes in rat brains following kainic acid induced seizure activity Objective: to study the change of C-FOS gene expression of hippocampal astrocytes in epileptic rat ,and explore relationship between C-FOS gene expression in astrocyte and epilepsy. Methods: C-FOS gene expression of hippocampal astrocytes in rat brains following kainic acid induced seizure activity was studied by double immunocytochemical staining. Results: The C-FOS gene expression in neurons and astrocytes of the CA1 area of hippocampus, perfectly in nucleus, was induced at 1h and obviously incleased at 6h after seizure activity. At 12h after seizure activity, the C-FOS-IR positive neurons decrease to control level, while a lot of C-FOS-IR positive astrocytes could be observed. The C-FOS-IR positive astrocytes returned to control level at 24h after seizure activity. Conclusion: the C-FOS-IR of astrocytes after seizure activity in our model show a kind of early and relatively sustained expression, which can prompt and retain expression of GFAP through the way of C-FOS/C-JUN . Expression of C-FOS gene may prompt and retain astrocytes active . This indicates that there is relationship between expression of C-FOS gene in astrocytes and relapse of epilepsy .