【摘要】 目的　观测 K物质对体外培养的乳鼠心肌细胞内游离钙离子浓度的影响 ,并探讨作用机制 .方法　应用钙离子荧光指示剂 Fluo- 3AM负载原代培养的大鼠心肌细胞 ,通过流式细胞仪检测心肌细胞内游离钙离子浓度 ([Ca2 + ]i)变化 ;分别应用速激肽受体拮抗剂 - DSP和抗水解 GDP类似物 -GDPβS,观察二者对 K物质诱导的 [Ca2 + ]i变化的影响 .结果　 SK能升高 [Ca2 + ]i,即由对照组的 173± 2 0 nmol· L- 1升高至 2 84± 2 0 nmol· L- 1 (P<0 .0 1) ,且在 1.78× 10 - 5～ 1.78×10 - 7mol· L- 1 浓度范围内存有剂量 -效应关系 ;DSP和GDPβS均可阻断 SK诱导的心肌细胞 [Ca2 + ]i升高的效应 .结论　SK可升高心肌细胞 [Ca2 + ]i,其作用有 G蛋白参与更多还原

【Abstract】 AIM To study the mechanism involved in SK induced increase of intracellular free calciumions in myocytes of rats. METHODS The fluorescent Ca 2+ indicator Fluo 3 was used to quantitate the calcium signal directly in the primary cultured myocardial cells by a flow cytometer and its signal transduction pathway was evaluated. RESULTS [Ca 2+ ]i in the SK group (284±20 nmol·L -1 ) was higher than in thecontrol group (173±20 nmol·L -1 ) ( P <0.01). SK elevated [Ca 2+ ]i in myocytes, in which a dose response relationship of SK at 1.78×10 -5 ～ 1.78×10 -7 mol·L -1 existed. The effects could be blocked by a tachykinin receptor antagonist DSP and non hydrolyzable GDP analoge GDPβS. CONCLUSION SK may elevate [Ca 2+ ]i in myocytes, which may be mediated by G protein.更多还原