目的研究山萘酚(Kaempferol,KA)、杨梅素(Myricetin,MY)、二氢杨梅素(Dihydromyricetin,DMY)、槲皮素(Quercetin,Qu)、二氢槲皮素(Dihydroquercetin,DQU)5种黄酮醇类化合物对大鼠心肌细胞内游离钙离子([Ca^2+]i)的影响。方法采用Fluo-3/AM同时加入PluronicF-127作为细胞内游离钙离子的荧光探针,负载H9C2心肌细胞系,应用激光扫描共聚焦显微技术,测定5种黄酮醇类化合物(50μmol/L)在静息状态和加入60mmol/L氯化钾(KCl)时心肌细胞胞浆内游离钙离子的荧光强度(FI)。结果静息状态下,KA和Qu能够明显降低心肌细胞内[Ca^2+]i(P〈0.05),MY能够短暂而明显升高[Ca^2+]i(P〈0.05),而DMY和DQU对心肌细胞内[Ca2+li无明显影响(P〉0.05);KA、MY、DMY、Qu和DQU对KCl介导的高钙有抑制作用(P〈0.05)。结论5种黄酮醇类化合物对电压依赖性钙通道(VDC)有明显抑制作用,这可能是产生药理活性机制之一.有利于进一步研究其对心肌的保护作用和探讨其构效关系。
Objective To investigate the effects of five flavonols on intracellular calcium concentration ([Ca^2+ ]i) in cardiomyocytes of rats. Methods Cardiomyocyte H9C2 of rats were loaded with Ca^2+ sensitive fluorescent indicator Fluo-3/AM ([Ca^2+ ]i). Fluorescent intensity (FI) was measured by laster scanning confocal microscopy at the states of resting and induced by 60 mmol/L KC1. Results At resting state, 50 μmol/L Kaempferol (KA) and Quereetin (QU) obviously decreased [Ca^2+]i(P 〈 0.05). Conversely, Myricetin (MY, 50 μmol/L) in Tyrode' s solution largely increased [Ca^2+ ]i (P 〈 0.05), then, Dihydromyricetin (DMY, 50 μmol/L) and Dihydroquertin (DQU, 50 μmol/L) were not affected [Ca^2+]i compared with the control(P 〉 0.05). The five flavonols all inhibited the increase of [Ca^2+]i induced by 60 μmol/L KC1 (P 〈 0.05). Conclusions These five flavonols inhibit voltage-dependent Ca^2+ Channel, which possibly contributes to protect the cardiomyocytes.