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Updated: Aug 21, 2026

Isolation of Human Atrial Myocytes for Simultaneous Measurements of Ca2+ Transients and Membrane Currents
Published on: July 3, 2013
Positive chronotropic and negative inotropic effects induced by potassium chloride in the isolated canine atrium
Abstract:
The effects of potassium chloride on inotropic and chronotropic activity were investigated in five isolated canine atrium preparations which were suspended in a bath and perfused with arterial blood from the carotid artery of the heparinized support dog. Potassium chloride administered into the cannulated sinus node artery in a dose range of 100 mug-1 mg produced a dose-related negative inotropic and a positive chronotropic effect. These effects were not influenced by treatment with either atropine or propranolol. From these results, it is concluded that potassium had a direct negative effect on atrial contractility and a direct positive effect on atrial rate.
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