1-磷酸鞘氨醇对心肌细胞钾离子通道的作用

目的：研究1-磷酸鞘氨醇（S1P）对豚鼠心室肌细胞延迟整流钾电流（IK）、内向整流钾电流（IK1）的作用。方法：实验用胶原酶酶解法急性分离豚鼠心室肌细胞,利用全细胞膜片钳的方法记录心室肌细胞的延迟整流钾电流（IK）、内向整流钾电流（IK1）。结果：①应用S1P（1．1μmol／L）后IK从（1．24±0．26）nA降至（0．95±0．23）以（P〈0．01,n=6）,而S1P（2．2μmol／L）组IK从（1．43±0．31）nA下降到（1．02±0．28）nA,统计学有显著性差异（P〈0．01,H=6）.而S1P（1．1μmol／L）＋苏拉明（Summin）（200μmol／L）组与对照相比,IK峰值从（1．29±0．26）nA下降（1．26±0．37）nA,统计学无显著性差异（P〉0．05,n=6）．②应用S1P（1．1μmol／L,2．2μmol／L）后与对照组比较,S1P（1．1μmol／L,2．2μmol／L）分别使内向整流钾电流（IK1）峰值从（-8．94±2．01）nA和（-8．81±1．55）nA下降到（18．86±1．59）nA和（-8．55±1．39）nA,统计学无显著性差异（P〉0．05,n=6）.结论：S1P可降低豚鼠心室肌细胞延迟整流钾电流（IK）的幅值,同时S1P对豚鼠心室肌细胞内向整流钾通道（IK1）没有作用。

The effects of Sphing-1-phosphate(S1P) on the potassium channel of the ventricular myocytes

Aim： To study the effect of Sphingosine-1-phosphate on the delayed rectifier potassium current（IK） and the inward rectifier potassium current（ IK1 ） of guinea pig isolated ventricular myocytes. Methods： Whole cell patch clamp technique was applied to record the delayed recti- fier potassium current and the delayed rectifier potassium current of guinea pig isolated ventricular Inyocytes. Results： （1）IK of SIP（ 1.1μmol/ L） decreased from （1.2± 0.26）hA to （0.95± 0.23）nA. While IK of S1P（2.2μmol/L） decreased from （1.43 ± 0.31）nA to （1.02 ± 0. 28） nA. There was significant difference compared to control group（ P 〈 0.01, n = 6）. The IK peak value was decreased from （ 1.29 ± 0.26） nA to （1.26 ± 0.37）nA at the group of S1P（1.1 μmol/L） plus suramin（200 μmol/L） and showed no significant difference compared to control group（ P 〉 0.05, n = 6）. （2）IK1 of S1P（ 1.1 μmol/L） decreased from （-8.94 ± 2.01）nA to （-8.81 ± 1.55）nA. While IK of S1P（2.2 μmol/L） decreased from （-8.86± 1.59）nA to （-8.55 ± 1.39）nA. There was no significant difference compared to control group（ P 〉 0.05, n = 6）. Conclusion： S1P inhibits delayed rectifier potassium current of ventricular myocyte in guinea pig remarkably, SIP shows no effects on delayed rectifier potassium current of ventricular myocyte in guinea pig.