赛庚啶对豚鼠心室肌细胞钙电流的影响  

Effects of cyproheptadine on Ca^(2+)current in guinea pig ventricular myocytes

作　　者：刘忠武[1] 任世兰[1] 唐明[2] 邹安若[2] 赵国举[1] 

机构地区：[1]同济医科大学郧阳医学院药理教研室,十堰442000 [2]同济医科大学生理教研室,武汉430030

出　　处：《中国药理学与毒理学杂志》1993年第2期122-125,共4页Chinese Journal of Pharmacology and Toxicology

摘　　要：应用全细胞记录式膜片钳技术研究了赛庚啶(Cyp)对豚鼠心室肌细胞慢钙电流(I_(Ca))的影响,Cyp 3和8μmol·L^1对I_(Ca)的电流-电压关系曲线(I-V曲线)之各电流均有降低作用,使I-V曲线上抬;在指令电位0 mV时,I_(Ca)为次最大值,Cyp 0.3～10μmol·L^1使该I_(Ca)呈浓度依赖性降低,IC_(50)值为1.98μmol·L^1,还观察到Cyp 1μmol·L^1明显增加外向电流(I_(out)),且四乙基铵(TEA)1 mmol·L^1对其有显著的拮抗作用,但对控制电位从80 mV跃升至-40 mV时所出现的瞬时快内向电流,无明显影响.以上结果直接证明了Cyp对心室肌细胞钙跨膜转运有明显降低作用,还可能增加钾外流。The effects of cyproheptadine(Cyp)on the slow Ca2+ currents(ICa)in a single guinea pig ventricular myocyte were studied using the whole cell recording patch clamp technique.Superfusion of cells with Cyp(3 and 8μmol·L-1)showed the inhibition of all the ICa which was elicited by depolarization from-30mV to +30 mV at 0.2 Hz and the uprising of current-voltage relationship curves(I-Vcurve).The I-V curve for ICa showed the next maximum values at 0 mV.This ICa was decreased by Cyp 0.3-10μmol·L-1 in a concentration-dependent manner.The half inhibition concentration(IC50)of Cyp was 1.98μmol·L-1 It has been observed that Cyp 1μmol·L-1 markedlyincreased the amplitude of outward current(Iout),while tetraethylammonium(TEA)exerted a significant antagonistic action on it.But on the fast inward current which had been elicited by a depolarization step from-80 mV to-40 mV,Cyp had no or little effect.The results demonstrate that Cyp depresses the transmembrane calcium current and may also enhance the K+ outward current in the ventricular myocytes.

关 键 词：赛庚啶 心室肌细胞 钙电流 

分 类 号：R965.1[医药卫生—药理学]