Pliam M B, Krellenstein D J, Brooks C M, Vassalle M
Basic Res Cardiol. 1977 Jan-Feb;72(1):34-45. doi: 10.1007/BF01906299.
The influence of norepinephrine on ventricular overdrive suppression and attendant potassium shifts has been studied in isolated perfused canine hearts with complete atrioventricular block. It was found that: 1) there is a potassium loss during the drive and a potassium uptake after the drive); 2) reducing the driving rate from 240 to 120/min decreases potassium loss; 3) norepinephrine increases potassium uptake and spontaneously beating ventricles and during the recovery from 120/min drive; 4) norepinephrine enhances K loss during and after a 240/min drive; 5) norepinephrine shortens the overdrive pause under all the conditions tested; 6) in ventricles driven at a constant rate, norepinephrine causes a small loss of ptoassium; 7) reserpinized hearts show a small potassium loss during drive and a larger potassium uptake after drive; yet, the suppression is longer; 8) norepinephrine increases K loss with drive and decreases overdrive suppression in reserpinized hearts; 9) norepinephrine enhances the increase in oxygen consumption caused by overdrive; and 10) norepinephrine antagonizes the depressant effect of high [K]0 on automaticity. It is concluded that norepinephrine shortens the pause independently of potassium levels and antagonizes the inhibittory influence of high K. The effect or norepinephrine on K movements depends on the ventricular rate and such rate-dependence is related to oxygen availability with respect to the increased metabolic demand.
在具有完全房室传导阻滞的离体灌注犬心脏中，研究了去甲肾上腺素对心室超速抑制及伴随的钾离子转移的影响。结果发现：1）在超速驱动期间有钾离子丢失，驱动后有钾离子摄取；2）将驱动频率从240次/分钟降至120次/分钟可减少钾离子丢失；3）去甲肾上腺素可增加钾离子摄取，在自发搏动的心室以及从120次/分钟驱动恢复期间也是如此；4）去甲肾上腺素在240次/分钟驱动期间及之后会增加钾离子丢失；5）在所有测试条件下，去甲肾上腺素都会缩短超速驱动后的停顿时间；6）在以恒定频率驱动的心室中，去甲肾上腺素会导致少量钾离子丢失；7）经利血平处理的心脏在驱动期间显示少量钾离子丢失，驱动后钾离子摄取量更大；然而，抑制时间更长；8）去甲肾上腺素在经利血平处理的心脏中会随着驱动增加钾离子丢失并减少超速驱动抑制；9）去甲肾上腺素会增强超速驱动引起的耗氧量增加；10）去甲肾上腺素可拮抗高[K]0对自律性的抑制作用。得出的结论是，去甲肾上腺素可独立于钾离子水平缩短停顿时间，并拮抗高钾的抑制作用。去甲肾上腺素对钾离子运动的影响取决于心室率，且这种心率依赖性与相对于增加的代谢需求的氧供应有关。
