| Objective:Epilepsy is a chronic disorder of the brain characterized by the imbalance of neurotransmitters and the abnormal discharge of the neuron. Temporal lobe epilepsy is one kind of the intractable epilepsy in adult, deeply investigation on temporal lobe epilepsy might be helpful on discovery the mechanism of intractable temporal lobe epilepsy. Complex endogenous self-acceleration and self-protection mechanisms are existed in brain in the procedure of temporal lobe epilepsy. GABA is essential in keeping the balance of excitation-inhibition, glutamate decarboxylase (GAD) is the rate-limiting enzyme of GABA synthesis, its distribution is parallel with GABA, the expression changes of GAD65 and GAD67 might reflect the functional status of GABAergic inhibition system. G-protein coupled inward rectify K(GIRK) current have the role on stabling neuronal membrane potential and development of postsynaptic inhibition, gap junction(GJ) formatted by gap junction proteins involve in the the procedure of neuronal synchronization of abnormal discharges. The different GAD65 and/or GAD67 changes due to all the datas were obtained with use of different models of epilepsy or different periods of epilepsy, and studies on the relations between GJB1 or GIRK1 and epilepsy are fewer, therefore, the present work was undertaken in order to study the dynamic changes in the expression of GJB1, GAD, GIRK1 inthe hippocampus of rats during different periods after kainate administration, systemically discuss the affect of GJB1,GAD, GIRK1 on endogenous self-acceleration and self-protection mechanism in hippocampus after seizures.Methods:1. Rats were injected with kainate 14mg/kg intraperitoneally to establish an acute and chronic temporal lobe epilepsy model. The rats were observed of occurrence of spontaneous recurrent seizures. The controls were injected with saline instead of kainate. At 3h, 6h, 12h, 24h, 48hours and 7. 30 days after kainate injection, the rats were anaesthetized and perfused, rats EEG were recorded antemortem.2 .By use of in situ hybridization, the GAD65, GIRK1, GJB1 mRNA were analyzed at different time quantitatively in the dentate gyrus, CA1, CA3 regions of hippocampus.3.GAD65, GAD67, GIRK1 protein in the various subfields of hippocampus were detected by immunohistochemistry at the same time points as set in situ hybridization. The results were analyzed quantitatively by image analytical system.Results:1.The succseed rate on establishment kainate-induced temporal lobe epilepsy is 79.8%, have no significant difference compared with documents. During different period, rats manifested SE or spontaneous recurrent seizures. Seizure-form discharges were recorded on the EEG during different periods in kainate groups while saline groups not.2.The expression of GJB1, GAD65, GIRK1 mRNA and GAD65, GAD67, GIRK1 proteins could be observed in all regions of hippocampus in both groups of rats. Positive cells in in situ hybridization looked as buffy or brown while in immunohistochemistry looked as royal blue.3. The GJB1 mRNA expression was increased significant at 6h-30d following the onset of seizure.4.Althrough there exist an increase tendency of the expression of GAD65 mRNA and its protein in hippocampus following seizures onset, only in the time point of 48h, 7d, 30d, the increase of GAD65 expression was significant, especially in 7-30 days.5.GAD67 protein was dramatically increased in hippocampus at 6h following the onset of SE, at 24h, another increasing occurred.6.The GAD67/GAD65 ratio was increased at 6h in CA1, CA3 regions following the onset of seizure, decreased at 30days in dentate gryus.7.The GIRK1 mRNA expression in dentate gyms was decreased significantly at 6h following the onset of seizure while increased at 7-30 days. The expression of GIRK1 mRNA in CA1, CA3 regions and its protein in hippocampus after seizures had no different compared with saline groups.8.At every time point, the expression of GJBlmRNA, GADmRNA and/or its protein, GIRK1mRNA in dentate gryus,...
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