基于多药转运体及钠通道的中药复方干预难治性癫痫大鼠耐药机制的研究

The main characteristic of intractable epilepsy (IE) is invalid by means of antiepileptic drugs (AEDs), which the key is resistance. Taking the idea that Xifeng Capsule, with functions of tonifying kidney essence、eliminating phlegm and calming down the wind, reducing phlegm and circulating collaterals, is effective to treat IE. We proposed the hypothesis that, “ the mechanism of Xifeng Capsule is inhibiting the over-expression of the multidrug transporter PGP, regulating the distribution and function of voltage-gated sodium channel by antagonizing neuronal damage in hippocampus; enhancing content of carbamazepine (CBZ ) in the brain and the sensitivity, thus achieving the purpose of reducing resistance”.This study planned to take the common experimental model of IE - pilocarpine epilepsy rat model, intending to take the mechanism of forming IE resistance as the starting point, considering pilocarpine IE rats' behavior change as effectiveness indicators, on basis of antagonizing neuronal damage in hippocampus, from aspects of the expression of multi-drug resistant (MDR) related gene mRNA and PGP, AEDs cerebrospinal fluid concentration, expression and function of VGSC related gene mRNA and protein ( current , current - voltage curve , activation curve and inactivation curve ), to study the anti-epileptic effect to IE rat and the mechanisms of influnce to resistance formation by traditional Chinese medicine —“Xi Feng capsules”.

难治性癫痫(IE)的主要特征是对多种抗癫痫药(AEDs)治疗无效，其原因关键在于耐药机制的形成。本课题组在既往证实益肾填精、豁痰熄风、化瘀通络之中药复方熄风胶囊治疗IE有效及相关机理研究的基础上，提出假说：“熄风胶囊治疗IE的作用机制可能与拮抗海马神经元损伤，抑制多药转运体P-糖蛋白（PGP）的过量表达，调节电压门控性钠通道(VGSC)的表达与功能，提高脑内卡马西平(CBZ)的含量，增强其抗痫敏感性等方面有关。”该研究拟采用IE的常用实验模型--匹罗卡品癫痫大鼠模型，以IE耐药机制形成为切入点，以病模大鼠行为学改变为效应指标，在拮抗海马神经元损伤基础上，从多药耐药（MDR）相关基因mRNA及PGP表达、AEDs脑脊液浓度、VGSC相关基因mRNA和蛋白表达及功能（电流、电流-电压曲线、激活曲线、失活曲线）等方面，研究熄风胶囊对IE大鼠的抗痫效应及影响IE耐药形成的作用机制。

难治性癫痫(IE)的主要特征是对多种抗癫痫药(AEDs)治疗无效，本课题组在既往证实益肾填精、豁痰熄风、化瘀通络之中药复方熄风胶囊治疗IE有效及相关机理研究的基础上，采用IE的常用实验模型--匹罗卡品癫痫大鼠模型，以IE耐药机制形成为切入点，以病模大鼠行为学改变为效应指标，在拮抗海马神经元损伤基础上，从多药耐药（MDR）相关基因mRNA及PGP表达、卡马西平（CBZ）脑脊液浓度、电压门控性钠通道（Ⅰ型钠通道α亚基蛋白、Ⅰ型钠通道α亚基蛋白基因mRNA、钠通道功能）方面，研究熄风胶囊对IE大鼠的抗痫效应及影响IE耐药形成的作用机制。实验结果显示熄风胶囊及联合CBZ对海马损伤有干预作用，起到保护海马神经元的作用；熄风胶囊可能通过抑制癫痫大鼠脑组织Pgp/MDR1mRNA的表达降低脑内AEDs 浓度，从而降低癫痫反复自发性发作；可以增加大鼠CBZ脑细胞外液的药物浓度，并且增加药物浓度的脑血比值；IE大鼠海马区Nav1.1的表达上调，熄风胶囊可能通过干预Nav1.1在IE大鼠海马区的分布及表达，减少钠通道电流，增强钠通道失活，抑制失活后的恢复，以此达到阻滞钠通道的作用，从而降低癫痫反复自发性发作，达到了本研究预期目的.充分发挥了中医药毒副作用小、多靶点、多途径的综合调节优势，为临床应用和进一步研究提供理论和实验依据。