The presence and properties of Mg 2+-HCO 3−-stimulated and SCN −-inhibited ATPase in mouse kidney and some relationships between ATPase and carbonic anhydrase

Abstract

1. 1. Mg 2+- and Mg 2+-HCO 3 −-ATPase activities from mouse kidney were highest in mitochondria. 2. 2. Optimal concentrations of Mg 2+ and HCO 3 − for Mg 2+-HCO 3 −-ATPase activity were 1.5 and 30 mM, respectively. 3. 3. Optimal pH value for maximum Mg 2+- and Mg 2+-HCO 3 −-ATPase activities was about 9.0 at 37°C. 4. 4. SCN − inhibited both Mg 2+- and Mg 2+-HCO 3 −-ATPase at concentrations above 10 −2 M. 5. 5. Mg 2+-HCO 3 −-ATPase had no direct relationship with adrenalectomy and aldosterone administration in contrast to carbonic anhydrase.