RESEARCHES ON THE PERFUSED HEART—SOME ACTIONS OF ACIDS AND ALKALIS

Abstract

Alkalis produce two types of ventricular contraction. The one produced by small concentrations of alkali (Gaskell) depends on the calcium salts in the perfusing medium; the other is not so dependent. It is an alkali rigor.Acids produce two main types of ventricular contraction. Certain organic acids produce a slow developing rigor contraction which destroys the contractile material.Certain inorganic acids produce a quickly developing contraction capable of repetition.Lactic acid produces a contraction of intermediate type.The perfusion of acids through the heart changes the normal reaction of the ventricular wall to sufficiently concentrated solutions of calcium or potassium salts. The change suggested is that of altering the permeability of some membrane or membranes to these salts.The physiological neutralisation of an acid is not adequately performed by a bicarbonate but it is by a phosphate.Under the conditions of these experiments the hydrogen ion adversely influences those functions of the heart subserved by the sarcoplasm and its junction with other contractile elements.The actions of the hydrogen ion are determined by the displacement of other inorganic elements in the tissues, calcium salts being important elements so displaced.