The Dynamic Expression Of Navl.2in The Hippocampus Of Rats With Temporal Lobe Epilepsy

Object To investigate the dynamic expression of Navl.2in the hippocampus of rats with temporal lobe epilepsy(TLE)Methods The149male Sprague-Dawley(SD) rats(weighted250±20g)were randomly divided into control group and TLE group.The rats in TLE group were injected lithium chloride and pilocarpine,while the control group received saline treatment instead of pilocarpine.We randomly chose6rats from the TLE group and3from control group to place hippocampal electrodes before giving lithium chloride, and recorded EEG at4stages as before giving lithium chloride, during SE,1day after SE, and7days after SE.The rest rats of TLE group and control group were randomly divided into5subgroups according to different time after SE,such as1day after SE,7days after SE,15days after SE,30days after SE,60days after SE. Then we sacrificed them at the defined time for further immunohistochemisty,Western blot and Quantitative real-time-PCR examination for studying Nav1.2dynamic expression in hippocampus.Results1.The lithium-pilocarpine model of TLE:SE was induced at the achievement ratio of79.21%and the total mortality was22.75%.2.The immunohistochemisty study showed that Navl.2mainly located in the cytomembrane and neuropil of hippocampal neurons. Comapred with control group, immunohistochemistry showed the expression of Navl.2in TLE group had no significant changes in regions of CA1, CA3and DG at1day,7days,15days or30days after SE (P>0.05);while60days after SE, the expression of Nav1.2was significantly decreased in regions of CA1and CA3(P<0.05), but no significant changes in DG areas (P>0.05).3.Western blot analysis showed Navl.2had no significant changes in hippocampus at all the time after SE,comparing with the control group(P>0.05).4.Quantitative real-time-PCR showed that compared with the control group,the level of Nav1.2mRNA had no significant changes in hippocampus at4stages as1day,7days,15days and30days after SE (P>0.05); while the level of Nav1.2mRNA was decreased in TLE group's hippocampus at60days after SE.Conclusions The expression of Navl.2was downregulated in the hippocampus at chronic phase of rats with TLE, which suggested Navl.2might play an important role in the chronic stage of spontaneous recurrent seizures in TLE...