THE EFFECT OF DIGITALIS ON THE RENAL TUBULAR TRANSPORT OF GLUCOSE IN NORMAL AND IN HEARTLESS DOGS

The effect of ouabain and acetylstrophanthidin on the renal transport of glucose and sodium has been measured in dogs in which all cardiac activity has been replaced by a mechanical intrathoracic pump ("heartless dog"). The drug activity on the heart is thus eliminated, and the effect of high concentrations is open to study. Both ouabain and acetylstrophanthidin depress the tubular reabsorption of glucose. Digitalis in very high doses produces complete renal shutdown. It is suggested that, as in the intestine, the sodium and sugar pumps are mutually dependent on pump adenosinetriphosphatase and that digitalis is effective through inhibiting this common mechanism. The heartless dog with circulation supported by a mechanical pump has proven to be a valuable pharmacologic preparation when cardiac activity must be differentiated from peripheral effects.