CAJ | 학술논문

目的研究花生四烯酸(arachidonic acid,AA)对家兔单个心室肌细胞L-广型钙通道的作用及其抗心律失常作用的机制.方法采用酶解法分离得到家兔单个心室肌细胞,全细胞膜片钳技术记录单个心室肌细胞L-型钙电流(L-type calcium current,Ica-L),用累积给药的方法在灌流液中加入不同浓度的AA,观察给药前后L-型钙电流的变化,统计学方法采用单因素方差分析.结果不同浓度的从均能明显抑制心室肌细胞,Ica-L.3 μmol/L,μmol/L,20,μmol/L的AA使Ica-L峰电流密度从(10.79±0.93)pA/pF分别减少剑(8.99 ±0.43)pA/pF、(7.60 ±0.35)pA/pF和(5.60±0.30)pA/pF(n=7,P<0.05),经冲洗后Ica-L可部分恢复,并且AA可使Ica-L的I-V关系曲线上移,其形状和峰值电压保持不变;20 μmol/L的AA使Ica-L失活曲线左移,失活后恢复时间明显延长,但对激活曲线无明显影响.结论花生四烯酸可通过加快L-型钙通道失活,延长其失活后的恢复过程而减少细胞外钙离子的内流,延长有效不应期,从而发挥抗心律失常作用.
목적 연구화생사희산(arachidonic acid,AA)대가토단개심실기세포L-엄형개통도적작용급기항심률실상작용적궤제.방법 채용매해법분리득도가토단개심실기세포,전세포막편겸기술기록단개심실기세포L-형개전류(L-type calcium current,Ica-L),용루적급약적방법재관류액중가입불동농도적AA,관찰급약전후L-형개전류적변화,통계학방법채용단인소방차분석.결과 불동농도적종균능명현억제심실기세포,Ica-L.3 μmol/L,μmol/L,20,μmol/L적AA사Ica-L봉전류밀도종(10.79±0.93)pA/pF분별감소검(8.99 ±0.43)pA/pF、(7.60 ±0.35)pA/pF화(5.60±0.30)pA/pF(n=7,P<0.05),경충세후Ica-L가부분회복,병차AA가사Ica-L적I-V관계곡선상이,기형상화봉치전압보지불변;20 μmol/L적AA사Ica-L실활곡선좌이,실활후회복시간명현연장,단대격활곡선무명현영향.결론 화생사희산가통과가쾌L-형개통도실활,연장기실활후적회복과정이감소세포외개리자적내류,연장유효불응기,종이발휘항심률실상작용.
Objective To study the influence of arachidonic acid (AA) on L-type calcium channel in rabbits sin-gle cardiomyocyte and its mechanism of antiarrhythmia. Method The single ventricular cardiomyocyte was isolat-ed by using enzyme dispersion method and whole-cell clamp-patch technique was used to record L-type calcium current.All data were analyzed using ANOVA. Results AA inhibited Ica-L in a concentration-dependent manner. The application of 3 μmol/L, 10 μmol/L and 20 μmol/L arachidonic acid reduced the density of peak Ica-L from (10.79±0.93)pA/pF to (8.99±0.43)pA/pF to (7.60±0.35)pA/pF and to (5.60±0.30)pA/pF, respctive-ly (n=7, P<0. O1 ). The Ica-Lpartially resumed after washout. The AA up-shifted the I-V curves of Ica-L without changes of their shape,peak and reverse potentials. The AA also markedly shifted the inactivation curve to left, and prolonged the recorvery time from inactivation,but did not change the curve of calcium channel activation. Con-clustions By acceleration of L-type calcium channel inactivation and prolongation of recorvery time from inactiva-fion,arachidonic acid can reduce the calcium ion influe and prolong effective refractory period, playing the role of antiarrhythmia.