苄基四氢巴马汀对豚鼠心室肌细胞钾电流及钙、钠电流的作用──谨以此文献给尊敬的老师江明性教授80寿辰

EFFECTS OF BENZYLENZYLTETRAHYDROPALMATINE(BTHP) ON POTASSIUM CURRENTS AND CALCIUM, SODIUM CURRENTS IN GUINEA PIG VENTRICULAR MYOCYTES

目的:研究苄基四氢巴马汀(BTHP)对心肌细胞的作用特点,以探讨其抗心律失常机制。方法:用全细胞膜片钳技术考察BTHP对心室肌细胞钾电流及钙、钠电流的作用。结果:BTHP30μmol·L-1明显阻滞延迟整流钾电流(IK包括:IKr及IKs)。可使IKr及IKr,tail的幅值下降,且对IKr阻滞作用呈频率依赖性;对IKs及IKs,tail幅值也有明显的抑制作用。BTHP200μmol·L-1可明显阻滞ICa,L,使其电流幅值降低,但对IK1,ICa,T,INa电流均无影响。结论:BTHP可明显阻滞心室肌细胞IKr,IKs,ICa,L电流,且对IKr阻滞作用呈频率依赖性。

AIM: To investigate the mechanism of antiarrhythmic action of benzylenzyl tetrahydropalmatine(BTHP). METHODS: The effects of BTHP on potassium currents, calcium and sodium currents were studied in guinea pig single ventricular myocytes by using whole cell patch clamp technique. RESULTS: BTHP was shown to effectively block the two components of delayed rectifier potassium( I K), ie I Kr and I Ks . I Kr and I Kr,tail were reduced from (0 68±0 27) pA/pF and (0 94±0 44) pA/pF to (0 47±0 18) pA/pF and (0 60±0 32) pA/pF, respectively by BTHP (30 μmol·L -1 ) in a frequency dependent fashion. I Ks and I Ks,tail were obviously inhibited from (12 1±1 78) pA/pF and (4 22±0 56) pA/pF to (7 25±0 87) pA/pF and (2 58±0 91) pA/pF after exposure to 30 μmol·L -1 BTHP. I Ca,L was also decreased from (14 48±0 26) pA/pF to (10 44±0 32) pA/pF by BTHP(200 μmol·L -1 ), but BTHP was shown not to affect I K1 , I Ca,T and I Na . CONCLUSION: BTHP significantly blocked I Kr , I Ks and I Ca,L , while I Kr was inhibited by BTHP in a frequency dependent fashion.