Hippocampus GLU γ-GABA Content Of Refractory Epilepsy And Drug Resistance Protein, Firewood Shellfish Soup Only Affect Epilepsy

The most important feature of intractable epilepsy (IE) is resistant to many kinds of antiepileptic drugs. Some studies suggested that multidrug resistance (MDR) genes and their coding proteins excessive expression should be one of the mechanisms of drug resistance. The up-regulation of P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) in IE patients and animals limit the AEDs concentration in epileptic focus. Therefore, the inhibitions of multidrug resistance proteins expression increasing the concentration of AEDs in the lesions brain tissue are becoming more and more popular in clinical domain. Chaibei Zhixian Decoction improves the efficacy of anti-epileptic drugs and the integrative treatment can reduce seizure frequencies and severity. So we conclude that Chaibei Zhixian Decoction down-regulate the levels of multidrug resistance protein at the blood-brain barrier and increase the concentration of antiepileptic drugs in intractable patients’brains. On the other hand, Chaibei Zhixian Decoction may regulate the balance between excitatory neurotransmitters and inhibitory neurotransmitters. Therefore, Chaibei Zhixian Decoction enhance the antiepileptic effects of antiepileptic drugs.Objective:In order to observe the antiepileptic effect of Chaibei Zhixian Decoction and investigate the mechanisms, this study will detect the protein and gene levels of BCRP and MVP after administrating with Chaibei Zhixian Decoction. Then, GLU concentration, y-GABA concentration, and the GLU/y-GABA ratio at rat hippocampal CA3region are our aims.Methods:Primary cultures of brain microvascular endothelial cells are prepared from rats, then the3rd passage cells are exposed to L-glutamate and dexamethasone to up-regulate the expression of P-gp/MDRl and BCRP respectively, which are up-regulation as multi-drug resistant epilepsy. After treatments, the solutions were replaced with a concentration (10μg/mL,100μg/mL,500μg/mL and1mg/mL) of Chaibei Zhixian Decoction for24h. Western blot is used for the measurement of P-gp and BCRP expression and real-time PCR is used for the determination of Mdrl mRNA and BCRP mRNA amplifications.This study rebuilt chronic intractable epileptic animal models with the method of injecting kainic acid in rat intracerebroventricular. Rats are divided into6groups randomly:normal group, sham group, model group, vehicle group, Chinese medicine group and integrative group. After3months treatment, Western blot are used to assess the expression of P-gp and BCRP in brain cortex and Realtime PCR are used to detect the amplifications of MDR1mRNA and BCRP mRNA.Microdialysis and HPLC are used to measure the concentration of GLU and γ-GABA. Results:(1) The P-gp expression of a concentration (100μg/mL、500μg/mL) of Chaibei Zhixian Decoction group is significant lower than that of model cell group(P<0.05); the Mdrla mRNA level of a concentration (100μg/mL,500μg/mL) of Chaibei Zhixian Decoction group is lower than model group(.P<0.05); the Mdrlb mRNA amplification of a concentration (500μg/mL) of Chaibei Zhixian Decoction group is lower than model group(P <0.05).(2) Exposure to Chaibei Zhixian Decoction(10μg/ml,100μg/ml)resulted in significant decrease in protein and mRNA levels of BCRP (P<0.05); While BCRP was down-regulated, NF-κBp65expression was decreased by Chaibei Zhixian Decoction(1mg/ml)(P<0.05).(3) Injecting kainic acid in rat intracerebroventricular can up-regulate the levels of BCRP and BCRP mRNA, MVP and MVP mRNA. Treatment with Chaibei Zhixian Decoction can decrease the expression of BCRP and BCRP mRNA (P<0.05). Chinese medicine group and integrative group can decrease the level of GLU/y-GABA ratio in CA3hippocampus (P <0.05).Conclusions:Chaibei Zhixian Decoction down-regulate the expression of BCRP at the blood-brain barrier and decrease the hippocampal CA3extracellular GLU/y-GABA ratio. These are the possible mechanisms of collaborative treatment.