摘要
用Fura-2/AM技术直接观察前胡丙素(Pra-C)对培养大鼠心室肌细胞内游离钙的影响。结果显示Pra-C浓度为0.1～1.0μmol·L^(-1)可明显抑制CaCl_2,高K^+和Bay K 8644引起[Ca^(2+)]i增加,并且有剂量—效应关系,对ouabain引起的[Ca^(2+)]i增加无明显作用。结果提示Pra-C降低心肌细胞[Ca^(2+)]i的作用与抑制电压依赖性钙通道有关。
The negative inotropic effect of Pra-C was supposed to be related to the blocking of extracellular calcium influx but direct evidence is not known. We, therefore, examined the effects of PraC on [Ca^(2+)] i in isolated rat ventricular myocytes using the fluorescent Ca^(2+)- indicator Fura-2/AM. It was found that Pra-C inhibited the elevation of [Ca^(2+)]i induced by potassiumdepolarization, high extracellular calcium and calcium agonist Bay K 8644 in a dose-dependent manner. At 1.0 μmol · L^(-1), it decreased the [Ca^(2+)]i at the presence of 75 mmol · L^(-1) KCl, 10 mol · L~^(-1) CaCl and 3 μmol · L^(-1) Bay K 8644 by 50, 31 and 42% respectively. No significant effect on ouabain evoked [Ca^(2+)]i increase was found, showing that it does not affect sarcolemmal Na^+ —Ca^(2+)exchange. These results further indicate that Pra-C may decrease the [Ca^(2+)]i of myocyte by blocking voltage-dependent calcium channels.
出处
《药学学报》
CAS
CSCD
北大核心
1993年第10期728-731,共4页
Acta Pharmaceutica Sinica
关键词
前胡丙素
心肌细胞
钙离子
前胡
Praeruptorin-C
Fluorescent Ca^(2+)- indicator Fura-2
Myocyte
Free calcium
Calcium antagonist
