双苯氟嗪对人心房肌纤维电生理的影响(英文)

Effect of dipfluzine on electrophysiology of human atrial fibers

用细胞内微电极技术记录心肌动作电位 ,研究双苯氟嗪 ( Dip)对人右心房肌纤维电生理特性的影响 .结果表明 ,Dip1 0 μmol·L-1显著降低舒张期自动除极速率 ( VDD)和自发搏动速率 ( RPF) ,分别从( 1 5.0± 2 .5) m V· s-1和 ( 30± 2 ) min-1降到 ( 1 0 .2± 1 .5) m V· s-1和 ( 2 2± 2 ) min-1;Dip 30μmol·L-1显著降低动作电位幅度 ( APA) ,0相最大上升速率( Vmax) ,VDD和 RPF,分别从 ( 63± 2 ) m V,( 9.2±2 .1 ) V· s-1,( 1 5.2± 3.3) m V· s-1和 ( 30± 2 )min-1降到 ( 52± 5) m V,( 6.5± 0 .9) V· s-1,( 7.0± 2 .6) m V· s-1和 ( 1 7± 2 ) min-1.但在所用浓度范围内对最大舒张电位无显著影响 .结果提示 ,Dip降低人心房肌纤维 APA,Vmax,VDD和 RPF,可能与其抑制 Ca2 +内流有关 .

The effect of dipfluzine(Dip) on the electrophysiologic characteristics of human right atrial fibers was studied using conventional intracellular microelectrode technique. The results showed that Dip 10 μmol·L -1 resulted in significant decreases in velocity of diastolic(phase 4) depolarization(VDD) and rate of pacemaker firing (RPF) from (15.0±2.5) mV·s -1 and (30±2) min -1 to (10.2±1.5) mV·s -1 and (22±2) min -1 , respectively. Dip 30 μmol·L -1 reduced markedly action potential amplitude(APA), maximal rate of depolarization in phase 0( max ), VDD and RPF from (63±2) mV, (9.2±2.1) V·s -1 , (15.2± 3.3) mV·s -1 and (30±2) min -1 to (52±5) mV, (6.5±0.9) V·s -1 , (7.0±2.6) mV·s -1 and (17±2) min -1 , respectively. Dip had no significant effect on maximal diastolic potential at any concentration used. It is suggested that Dip reduce APA, max , VDD and RPF in a concentration dependent manner in human atrial fibers, which may be attributed to its blocking effect on Ca 2+ influx.