关键词: 磷脂酸类, 膜片钳术, 心肌

Abstract: Objective To study the effects of exogenous phosphatidic acid (PA) on calcium current of ventricular myocytes.Methods The Langendorff perfusion method was used to isolate the ventricular myocytes of guinea pigs and the ventricular myocytes of guinea pigs were randomly divided into control group, three dosage groups of PA 0.01, 0.1 and 1.0 μmol ·L^-1and group of PTX 0.1 mg ·L^-1 plus PA 1.0 μmol·L^-1and group of H-7 2 μmol·L^-1plus PA 1.0 μmol·L^-1. The whole cell voltage clamp technique was used to record the calcium current of isolated ventricular myocytes of guinea pigs. Results 0.01, 0.1 and 1.0 μmol·L^-1 PA enhanced the calcium current from （288.70±28.33）pA,（290.83±25.12）pA and（279.54±31.22）pA before administration to（304.10±28.31）pA（P>0.05）,（349.80 ±30.13）pA (P<0.01) and（388.10±28.12）pA (P<0.001) after administration. The effects of PA on the calcium current was blocked by PTX (a G protein-coupled receptor blocking agent) and H-7 (a PKC blocking agent). Conclusion PA can promote the opening of calcium channels of the ventricular myocytes by the pathway of membrane receptor-G protein-PKC in a dose-dependent manner.

Key words: phosphatidic acids, patch-clamp technique, myocardium