[HCO3- -stimulated ATPase of rat kidneys]

In homogenate and mitochondria of cortex and medulla of rat kidney a stimulating effect of different concentrations of bicarbonate on the ATPase activity was studied. By the rate of inhibition of Mg2+-ATPase and HCO3-ATPase, thiocyanate, perchlorate and azide were distributed as follows: N3 greater than CNS greater than ClO4. Thiocyanate inhibited non-competitively the HCO3-stimulated ATPase activity. The similarity was observed between HCO3-stimulated ATPase from rat kidney and bicarbonate-stimulated ATPase from other cells.