【摘要】 槲皮素广泛存在于许多药用植物中,属黄酮类化合物,在临床上常用于心血管疾病的治疗。采用四甲基偶氮唑盐比色法(MTT法)及DAPI染色,研究槲皮素(0.5、1、5、10μmol/L)对谷氨酸(10mmol/L)诱导的PC12细胞损伤作用的影响;并进一步研究槲皮素(0.3、3、30μmol/L)对急性分离的海马CA1锥体神经元离子通道的作用。MTT实验结果显示,槲皮素可提高谷氨酸处理组PC12细胞的存活率,并呈现为浓度和时间依赖性(P<0.05);而槲皮素(5μmol/L)与谷氨酸(10mmol/L)共孵育PC12细胞后,DAPI染色结果表明槲皮素可减弱谷氨酸对PC12细胞的损伤。对电生理结果显示,槲皮素对瞬时外向钾电流(IA)和延迟整流钾电流(IK)有显著的抑制作用(P<0.05),表现为浓度依赖性。以上结果提示,槲皮素可能通过抑制海马锥体神经元的外向钾电流进而对谷氨酸诱导的神经损伤起保护作用,这也说明了槲皮素对缺血样损伤的神经具有保护作用。更多还原

【Abstract】 Quercetin is a flavonoid compound found in a number of medicinal plants that are often prescribed in Chinese clinics for the treatment of cardiovascular diseases.In the present study,the effects of quercetin(0.5,1,5 and 10 μmol/L) on PC12 cell toxicity,induced by glutamate(10 mmol/L),were investigated by MTT assay and DAPI staining.Additionally,the electrophysiological effects of quercetin(0.3,3 and 30 μmol/L) on cation channel were measured in acutely isolated rat hippocampal CA1 pyramidal neurons.The data of MTT assay showed that quercetin increased cell viability of PC12 cells exposed to glutamate(10 mmol/L) in a dose-and time-dependent(P<0.05);and the results of DAPI staining showed that quercetin reduced the damage caused by glutamate when PC12 cells were co-incubated with quercetin(5 μmol/L) plus glutamate(10 mmol/L).Further,quercetin significantly inhibited transient outward potassium currents(IA) and delayed rectifier potassium current(IK) in a concentration-dependent manner(P<0.05).Taken together,the data presented in this study first revealed that quercetin inhibited IA and IK in neurons in hippocampal neurons,protected cell from glutamate-induced injury,which provides an explanation for the neuroprotective effects of quercetin against ischemia like injury.更多还原