[Activity and properties of adenosine triphosphatase in erythrocytes and various tissues (brain, liver, kidney, small intestine mucosa) of cattle].

In 15 samples of haemolysate of bovine erythrocytes, the splitting of phosphate from adenosine triphosphate average 158 +/- 63 X 10(-3) muMol/min/g haemolysate haemoglobin. Estimation of total adenosine triphosphatase in homogenates of various organs from cattle showed that spleen, liver, kidney and brain possessed high activity, while the activity was moderate in lung, myocardium and skeletal muscle, and low in endometrial mucosa and spinal cord. There was a relatively large proportion of Na-K-adenosine triphosphatase in brain and kidney. In various organs the activity of the enzyme was dependent upon the concentrations of Mg, Na, K and Ca. The inhibition of adenosine triphosphatase in various tissues by ouabain was studied. The optimum pH for the enzyme lay in the weakly alkaline region.