Kones R J
Int J Clin Pharmacol Biopharm. 1976 Jun;13(4):269-91.
Potassium is an important electrolyte in heart cells and has the greatest membrane permeability in the unexcited state. Hence it is responsible for th generation of the resting membrane potential. Clinical disorders of conduction and impulse formation occur within physiological values of serum potassium. Potassium is indirectly involved in excitation-contraction coupling, and its relation to intracellular calcium metabolism is reviewed. While potassium movements within the cell are metabolic-dependent, it is also true that the activity of metabolic pathways is affected by changes in potassium concentration. During anoxia and ischemia, sodium and calcium are gained by the myocyte, and potassium and magnesium are lost by the cell. At the same time, the action potential duration is abbreviated, the slope of the action potential downstroke (phase 2) is increased, and the resting membrane potential may be reduced. A relationship between disturbances in intracellular potassium and ischemic arrhythmias appears likely.
钾是心脏细胞中的一种重要电解质，在未兴奋状态下具有最大的膜通透性。因此，它负责静息膜电位的产生。传导和冲动形成的临床紊乱发生在血清钾的生理值范围内。钾间接参与兴奋-收缩偶联，本文对其与细胞内钙代谢的关系进行了综述。虽然细胞内钾的移动依赖于代谢，但代谢途径的活性也确实会受到钾浓度变化的影响。在缺氧和缺血期间，心肌细胞摄取钠和钙，细胞丢失钾和镁。同时，动作电位时程缩短，动作电位下降支（第2相）的斜率增加，静息膜电位可能降低。细胞内钾紊乱与缺血性心律失常之间似乎存在关联。
