The Study Of Effects Of Child Niuhuang Qingxin Powder On Seizuresand Brain Injury In Developing Rats

PART ANTICONVULSIVE EFFECTAND POSSIBLEMECHANISM OF CHILD NIUHUANG QINGXINPOWDER ON SEIZURES IN INFANTALRATSObjective: To observe the anticonvulsant action of Child NiuhuangQingxin Powder (CNQP) in the infantal rats. To explore the effect of ChildNiuhuang Qingxin Powder on the changes of cerebral cortex andhippocampal glutamate and GABA releases and the associated EPSC andIPSC in thedeveloping rats after induced seizure.Methods:(1)In order to observe the anticonvulsant action of CNQPin the infantal rats,One hundred and twenty juvenile Sprague-Dawley(SD)rats were equally randomized into two main groups including the vivogroup and brain slice group.1)The vivo group were divided into6sub-groups including the normal control group，seizure control group，diazepam treated group， low-dose、 middle-dose、 high-dose of CNQPtreated group, and each subgroup contained10rats. The rats were respectively orally pretreated with4ml saline/d，CNQP of300mg/kg/d,8g/kg/d and16g/kg/d，diazepam5.264mg/kg/d twice for one day，andinjected intraperitoneally with a dose of70mg/kg of pentylenetetrazole（PTZ）30min after the administration of the drug for the second timeexcept the rats in the normal control group.The convulsive behaviorsincluding the latent period，seizure time,seizure score, simultaneousEEG,mortality was observed for30min after each injection.2）Therats in the brain slice group were orally pretreated the same as vivogroup.They were made into brain slices30min after the administration ofthe drug for the second time and the slices were induced by Mg2+freeACSF for the record of field potential of the cortex and CA1region of thehippocampus including the latent period, frequency and amplitudeof wave.(2)Another200juvenile Sprague-Dawley(SD) rats were equallyrandomized into5groups：the normal control group，the seizure controlgroup，low-dose、middle-dose、high-dose of CNQP treated group.Theywere administrated the same as the above rats.The changes of cerebralcortex and hippocampal glutamate and GABA were detected by HPLC atthe time point of30min and3h after the injection of PTZ in eachgroup.The spontaneous EPSC and spontaneous IPSC were also detectedby whole cell patch clamp at the same time point in each group.Results: CNQP significantly prolonged the latent period of seizures,delayed the seizure time,decreased the seizure score and mortalityof the rats and improved the EEG at high-dose and middle-dose（p＜0.01）.It also decreased the seizure rate and prolonged the latent period of seizures,decreased frequency and amplitude of wave induced by the Mg2+freeartificial cerebrospinal fluid (ACSF) of brain slice at high-dose andmiddle-dose. CNQP could not only reduce the glutamate content and thespontaneous EPSC in cerebral cortex and hippocampal but also couldincrease the GABA content in the cerebral cortex and hippocampal dosedependently.Conclusions: CNQP has possessed anticonvulsant activity againstpentylenetetrazole induced and Mg2+free artificial cerebrospinal fluidinduced seizures dose dependently in the infantal rats.Theanticonvulsant effect of the drug on seizure is probably related with themodulation of the balance of excitatory amino acid and inhibitory aminoacid and the associated spontaneous EPSC and IPSC. PART THE EFFECT OF CHILD NIUHUANGQINGXINPOWDER ON THE BRAIN INJURY OF SEIZURES IN THEDEVELOPING RATSObjective: To study the protective effect of CNQP against brain injuryof pentylenetetrazole-induced seizure.Methods: Juvenile Sprague-Dawley(SD) rats were equallyrandomized into5groups，the normal control group，seizure controlgroup， low-dose，middle-dose and high-dose of CNQP group, whichwere given orally with4ml saline/d,CNQP of16g/kg/d，8g/kg/d，0.3g/kg/d，respectively，twice for one day，except the normal controlgroup. After the injection of PTZ,rats in all groups were sacrificed inproper times for the pathological inspection of brain tissues. Apoptoticneurodegeneration index in the cortex and CA1region of the hippocampuswere examined by TUNEL assay.The expression of IL-1β and glialfibriliary acidic protein (GFAP) in the cortex and CA1region of thehippocampus were also observed by immunohistochemistry.Results: No significant difference was observed between the H-CNQPgroup and the normal group in the expression of IL-1β and GFAP and theapoptotic index. But the expression of IL-1β and GFAP and the apoptoticindex of H-CNQP treated group were higher than these of the normalcontrol group and lower than those of the seizure control group（p＜0.05）. No significant difference were observed between the L-CNQP and theseizure control group in the expression of IL-1β and GFAP and theapoptotic index.Conclusion: CNQP can protect the immature brain from the injury ofseizures dose dependently.And the mechanism may be about the decreasedof IL-1β in the cortex and CA1region of the hippocampus.