| Epilepsy is one of the most common diseases of the nervous system, andnearly900million people have gotten epilepsy in China. The first choice oftreatment for epilepsy is medication, but about1/3of the patients are poorreactive to variety of drug treatments and become refractory epilepsy. Refractoryepilepsy patients taking the maximum tolerated dose and plasma concentrationhave been keeping the effective range, but still can’t control the seizures ofrefractory epilepsy, which affect patients daily lives.Pathogenesis of epilepsy is still unknown, but the theory of epilepsy iscaused by neurons abnormal discharge is widely accepted. Glucose metabolismof patients with epilepsy is low in interval of attack, but positron emissiontomography (PET) imaging shows high glucose metabolism during attack. This evidence suggests the seizure may be related to glucose metabolism. It isrecognsphorylation of α1subunit plays a critical role in the functionalmaintenance of the GABA_Areceptor. The phosphorylation of α1subunit ofGABA_Areceptor depends on the function of GAPDH in glucolysis in thepresence of Pi, NAD+, NADH and G-3-P. Therefore glucose metabolism islinked closely to epilepsy, and especially NADH may have effects on epilepsyseizures with regulating function of GABA_Areceptor. The rat suffered epilepsyinduced by the Lithium Chloridec-Pilocarpine is considered as epileptic ratmodel because whose characteristics are similar with the human temporal lobe,and Spontaneous seizures (SRS) that happen in this mode l is very similar tohuman status epilepticus in EEG, and various anti-epileptic drugs can fightagainst this epileptic seizures. In animal models of epilepsy, Lithium Chloride–Pilocarpine model is an ideal recognized animal model in limbic system epilepsy.The acute epilepsy model is established using rat injected with Lithium Chloride-Pilocarpine intraperitoneally.Objective To introduce the establishment of lithium chloride-pilocarpineinducing epilepsy rat model, and with the whole-cell patch clamp recordings, wepreliminarily studied on GABA_Areceptor function of entorhinal cortical neuronsin epileptic rats at first. Then we studied on NADH as a hydrogen donor toparticipate in a variety of metabolic reactions in vivo, and illustrated the neuronenergy metabolism how to affect the GABA_Areceptor function secondly.Exploring and enriching the pathogenesis of epilepsy may provide new ideasand methods for the clinical treatments for epilepsy.Method Experiment I:30Spraque-Dawley (SD) rats were randomlydivided into epilepsy model group (20) and normal saline group (10). Epilepsymodel rats had been intraperitoneal injected of lithium chloride and pilocarpine. Rats seizures symptoms analysis was quoded vide Racine Grading Standards.The rat which achieved Racine Level IV and survival was included in epilepsygroup. The rats of control group received the same volume of saline byintraperitoneal injection. All of rats were anesthetized and rapidly decapitatedand obtained brains. Then6-8entorhinal cortex brain slices were got by avibrating slicer. With whole-cell recording under voltage clamp Gapfree mode,we recorded the GABA_Areceptor currents administered GABA10sec every2min for12min.Experiment II:45Spraque-Dawley (SD) rats were randomly divided intoNADH group (15) and non-intervention group (15) and control group (15). Allrats had intraperitoneal injection of Lithium Chloride and Pilocarpine. Modeling,and taking brain, preparation of brain slices and electrophysiological recordingwere in accordance with the experimental I. Each group was administered of thepipette solution. Intracellular fluid of NADH group was added in NADH and ofcontrol group was added in Okadaic Acid.Results Experiment I: The neurons GABA_Areceptor currents of epilepsyrats decayed with time obviously and of the saline group rats decayed notsignificantly. Under standardized recording conditions, we took data of20ratsboth of model group and control group to compare in the scope of the statistics.The GABA_Areceptor currents of model group decayed more significantly thanthe one in saline group. The differences between groups (p<0.001) and times(p<0.05) were significant by variance test and interclass analyses, and the dataof every point of time in experiment group and control group also havesignificant difference by t-text analyses (P<0.001).Experiment II: GABA_Areceptor current of non-intervention group andcontrol group decayed with time obviously and of the NADH group rats decayed with time not significantly. Under standardized recording conditions,we took data of15rats from NADH group, non-intervention group and controlgroup to compare in the scope of the statistics. GABA_Areceptor current decayrate significantly were reduced in NADH group than the other two groups. Thedifferences between groups (p<0.001) and times (p<0.05) were significant byvariance test and interclass analyses, and the data of every point of time inexperiment group and control group also have significant difference by t-textanalyses (P<0.001).Conclusion Lithium chloride-pilocarpine epilepsy model inducedepilepsy rat of spontaneous seizures (SRS), of which mechanism is yet unclear.In this experiment, epilepsy rats GABA_Areceptor current decay tendency wereenhanced significantly than normal group, indicating that GABA_Areceptorfunction were impaired in this rat model. So injuries of GABA_Areceptorfunction may be the electrophysiological mechanism of lithium chloride-pilocarpine induced epilepsy.NADH hydrogen donor can be involved in variety of metabolic reactions invivo. In this study, NADH can inhibit current decay of GABA_Areceptor inepileptic rat within a certain extent, indicating that NADH may repair thedamages of GABA_Areceptor function, and terminate epilepsy seizures. |
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