论文部分内容阅读
目的:研究蜂毒肽(Melittin,Mel)对豚鼠心室肌细胞钾电流和动作电位的影响.方法:全细胞膜片箝记录.结果:蜂毒肽可呈浓度依赖性促进延迟整流钾电流(I_k),在测定电压为40 mv时,0.05,0.1,0.2μmol·L~(-1)蜂毒肽分别使I_k从(295±109)增大到(371±142)(n=5 P<0.05),(467±180)(n=5,P<0.05),(552±248)pA(n=5,P<0.05).但药物在三个浓度时对内向整流钾电流(I_(k1))均无显著影响.蜂毒肽0.05,0.1,0.2 μmol·L~(-1)分别使动作电位APD_(50)由(520±55)减小到(459±91)(n=5,P>0.05),(385±102)(n=5,P<0.01),(281±81)ms(n=5,P<0.01),使APD_(90)由(613±96)减小到(536±93)(n=5,P>0.05),(467±96)(n=5,P<0.01),(354±95)ms(n=5,P<0.01).结论:蜂毒肽促进延迟整流钾电流,缩短动作电位时程.
Objective: To study the effect of Melittin on potassium currents and action potentials in guinea pig ventricular myocytes.Methods: Whole-cell patch-clamp recordings were performed.Results: Melittin could delay the delayed rectifier potassium current (I_k) in a dose- At the voltage of 40 mv, 0.05, 0.1, 0.2 μmol·L -1 melittin increased I_k from (295 ± 109) to (371 ± 142) (n = 5 P <0.05) , (467 ± 180), (552 ± 248) pA (n = 5, P <0.05) (P <0.05), and the APD 50 (50) of melittin decreased from (520 ± 55) to (459 ± 91) (n = 5, P> 0.05), (385 ± 102) (n = 5, P <0.01), (281 ± 81) ms (n = 5, P <0.01) and APD 90 decreased from (613 ± 96) to (N = 5, P> 0.05), (467 ± 96) (n = 5, P <0.01) and (354 ± 95) ms Delayed rectifier potassium current, shorten the action potential duration.