CAJ | 학술논문

目的研究犬窦房结细胞起搏电流动力学特点,并与乳鼠心肌细胞表达野生型超极化激活环化核苷酸门控(mHCN2)通道比较. 方法用含胶原酶、弹性蛋白酶的无钙溶液酶解犬窦房结细胞,分离并记录窦房结细胞起搏电流,并在相同实验条件下与乳鼠心肌细胞表达野生型mHCN2通道电流的激活动力学比较. 结果犬窦房结细胞的形态为长梭形或多边形,边缘清楚,有自发性搏动,犬窦房结细胞的起搏电流是内向电流,并随着超极化电位的增加,电流增加幅度明显加快,在V=-75 mV,窦房结起搏电流为(-2.1±0.3)pA/pF,犬窦房结细胞起搏电流激活较mHCN2通道电流激活接近,通道激活时间常数分别为(728±137) ms、(530±65) ms,(P＞0.05). 结论生理范围内犬窦房结细胞起搏电流和乳鼠心肌细胞过表达野生型mHCN2通道电流有类似激活动力学.
목적 연구견두방결세포기박전류동역학특점,병여유서심기세포표체야생형초겁화격활배화핵감산문공(mHCN2)통도비교. 방법 용함효원매、탄성단백매적무개용액매해견두방결세포,분리병기록두방결세포기박전류,병재상동실험조건하여유서심기세포표체야생형mHCN2통도전류적격활동역학비교. 결과 견두방결세포적형태위장사형혹다변형,변연청초,유자발성박동,견두방결세포적기박전류시내향전류,병수착초겁화전위적증가,전류증가폭도명현가쾌,재V=-75 mV,두방결기박전류위(-2.1±0.3)pA/pF,견두방결세포기박전류격활교mHCN2통도전류격활접근,통도격활시간상수분별위(728±137) ms、(530±65) ms,(P＞0.05). 결론 생리범위내견두방결세포기박전류화유서심기세포과표체야생형mHCN2통도전류유유사격활동역학.
Objective To investigate the dynamic characteristics of the pacemaker current of canine sino-atrial node cells and compare them with the wild type mHCN2 pacemaker current overexpressed in neonatal rat myocardial cells.Methods Fresh canine sino-atrial node cells were enzymatically isolated in a calcium-free solution containing collagenase and elastase,and the funny current was recorded and compared with the mHCN2 current overexpressed in cultured neonatal rat myocardial cells under the same experimental conditions.Results The canine sinus node cells were elongated,spindle-shaped or polygonal,with well-defined boundaries,and showed spontaneous beating.The elicited pacemaker current was an inward current and its rise in amplitude quickened as the hyperpolarization potential increased.At V ＝-75 mV,the canine sinus atrial node pacemaker current was (-2.1±0.3) pA/pF and had the same activation kinetics as those of the mHCN2 channel current overexpressed in neonatal rat myocardial cells [τact:(728±137) ms vs.(530±65) ms,P＞0.05].Conclusions Within the physiological range,the pacemaker current in canine sino-atrial node cells and the wild type mHCN2 pacemaker current over expressed in neonatal rat myocardial cells have similar activation kinetics.