Role of Chloride Ions in Cardiac Action and Pacemaker Potentials.
نویسنده
چکیده
DE MELLO, WALMOIC CARLOS. Role of chloride ions in cardiac action and pacemaker potentials. Am. J. Physiol. 205(s) : 567-575. 1 g63.-Evidence is presented that chloride ions are able to carry an appreciable amount of electric charge through the membrane of atria1 muscle fibers, Purkinje fibers, and fibers of the S-A nodal pacemaker. An increase in the slope of diastolic depolarization of pacemaker fibers was recorded when Clwas replaced by larger anions (sulfate) in the external medium. The rate of repolarization decreased when larger anions were substituted for chloride ions, and it was increased in nitrate or bromide solutions. The anionic permeability of the cell membrane of S-A node, atria1 muscle, and Purkinje fibers seems to follow the series:
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ورودعنوان ژورنال:
- The American journal of physiology
دوره 205 شماره
صفحات -
تاریخ انتشار 1963