Study On The Effect Of Quinine On The Expression Of Connexin36 Junction And Pannexin-1 In Hippocampus Of Penicillin-induced Seizure Rats

Objective:Gap junctions was considered to play an important role in the process of epilepsy. Application of Cx (connexin, Cx) 36 channel blocker quinine is thought to have anti-epileptic activity in theory.In this study, we used hippocampal microinjection of penicillin to set up acute epilepsy model, and treated with quinine intervention in vivo.To investigate the effect of quinine on the expression of connexin36 junction and pannexin-1 in hippocampus of penicillin-induced seizure rats and epilepogenesis on seizure activity in rats,behaviors of the rats was observed,electroencephalogram was introduced to record electrical activity of rat cortex,the expression of Cx 36 and Pxl in hippocampus neurons in each group was determined by using immunohistochemistry.Methods:Using brain stereotactic apparatus, the acute seizure model was prepared on the right hippocampus of rats micro injected with penicillin.35 Sprague-Dawley (SD) rats were randomly divided into 3 large groups,7 subgroups and each group had 5 SD rats. As follows:1.Mold control groups(A):including 5 rats,the same dose of normal saline was only microinjected on the right hippocampus and the rats were sacrificed at 24h.2.Penicillin-induced seizure model group(B):including 15 rats,1 hour after seizure onset subgroup(B1),3 hour after seizure onset subgroup(B3), 24 hour after seizure onset subgroup(B24),each group had 5 rats.The rats were sacrificed at 1,3,24h.3.Qunine interfering group(C):including 15 rats, quinine (50mg/kg i.p.) injected 20 min before the administration of penicillin,and it also includes the 1st hour(C1),3rd hour(C3) and 24th hour(C24) three subgroups,each group had 5 rats.The rats were sacrificed at 1,3,24h.The latency period and amplitude of seizure, the waveform characteristic and epileptic wave frequency on EEG, the expressions of Cx36 and Px1 of hippocampus neurons were observed. Results:The expressions of Cx36 in hippocampus neurons showed that increased at 1 hr, and decreased at 24 hr, However, there was a significant difference than that in control group at the same time point(P<0.01), The expression of Cx36 was also visibly increased in quinine group than that in control group(P<0.05),but it was lower when compared with model group B(P<0.05).The expressions of Pxl in hippocampus neurons was significantly increased in group B and group C, when compared with control group (P<0.05).But there was no significant difference between group B and group C.The intensity of seizures activity reached the peak at the 3rd hour in penicillin-induced epileptic rats, and the latency was longer in group C than that in group B; epileptic discharge could be recorded on the EEG in group B and C, and the frequency of epileptic waves were decreased after the treatment of qunine in group B;Conclusions:1.The expression of Cx36 and Px1 in hippocampal neurons of penicillin-induced epileptic rats were both significantly increased, indicating that both may participate in the pathogenesis of epilepsy;2 Quinine significantly inhibited the expression of Cx36, extended the latency of epileptic seizures, indicating that it may have the potential anticonvulsant effect.