Content of Inorganic and High Energy Phosphates, Potassium, Sodium, Lactate and Glycogen in Different Areas of the Dog Heart

Concentrations of inorganic phosphate, phosphocreatine, adenosine polyphosphate and potassium were all lower in atrial than in ventricular tissue by approximately 40%. Sodium concentration, in contrast, was higher by 60%. In right atrium, phosphocreatine, adenosine polyphosphate and potassium concentrations were all about 20% lower than in left atrium. Nonspecific factors such as variation in extracellular space or in connective tissue content are believed to be responsible for these results. Slightly higher phosphocreatine and glycogen values in right ventricle in contrast to the left may be related to functional differences in the muscle cells in these areas.