1-磷酸鞘氨醇对心肌细胞内游离钙离子浓度的影响

目的研究1-磷酸鞘氨醇（sphingosine-1-phosphate，SIP）对体外培养的乳鼠心肌细胞内游离钙离子浓度的作用。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，通过激光共聚焦扫描显微镜上机检测，记录其荧光强度变化。结果@SIP能降低[Ca2＋]i平均荧光强度值，对照组由（743．15±34．78）nmol／L降至（446．89±55．36）nmol／L（P〈O．01，n=7）；而S1P（1．1μmol／L）＋苏拉明（Suramin）（200μmol／L）组[ca2＋]i平均荧光强度值由（778．39±42．15）nmol／L降至（759．41±38．17）nmol／L，差异无统计学意义（P〉O．05，n=7）。结论S1P可降低乳鼠心肌细胞内游离钙离子浓度，这种作用可能通过其特异性的G蛋白耦联S1P受体介导产生。

The effects of sphing-1-phosphate(S1P)on the intracellular free calcium concentration of cultured ventricular myocytes

Objective To study the effect of Sphingosine-l-phosphate（S1P） on intracellular free calcium concentration of cultured ventricular myocytes. Methods The fluorescent Ca2＋ indicator Fluo-3 was used to quan- titate the calcium signal directly in the primary cultured myocardial cells by LSCM continuous scanning. Results The intracellular free calcium concentration was decreased significantly compared with control group. After adminis- tered S 1P （1.1 μmol/L）, the average intracellular free calcium concentration decreased from （743.15±34.78）nmol/L to （446.89＋55.36）nmol/L（P〈O.O1, n=7）, meanwhile, in group of SIP （1.1 μmal/L） plus suramin （200 μmol/L） there showed no significant difference compared to control group （P〉O.05, n=7）. Conclusion The above results suggested that SIP decrease intracellular free calcium concentration of cultured ventricular myocytes.It＇s mechanism may concern coupling of G-protein and SIP receptor.