TY - JOUR T1 - THE MODE OF ACTION OF POTASSIUM UPON ISOLATED ORGANS JF - Journal of Pharmacology and Experimental Therapeutics JO - J Pharmacol Exp Ther SP - 423 LP - 447 VL - 18 IS - 6 AU - A. J. CLARK Y1 - 1921/12/01 UR - http://jpet.aspetjournals.org/content/18/6/423.abstract N2 - Rubidium acts as a perfect substitute to potassium in all of the isolated tissues examined; caesium acts as an imperfect substitute; thorium and uranium do not act as substitutes to potassium, but they act as irritants to the frog's heart and will induce automatic beats in hearts arrested by lack of potassium. The expenses of this research were defrayed by a grant from the Royal Society. ER -