[Effect of monovalent and bivalent cations and anions on the properties of ATPase from rabbit small intestine mucosa].

The effects of monovalent cations and anions on the ATPase activity of rabbit small intestine mucosa membranes was studied. It was shown that the small intestine mucosa contains the ATPase activity sensitive to NaCl and NaHCO3. This activity, in contrast to the HCO3--ATPase activity, is inhibited by ethacrinic acid, is practically insensitive to thyocyanate, has a pH optimum of 6.2, is unstable upon storage and is not inhibited by 2 mM EDTA. The catalytic and regulatory properties of HCO3--ATPase and NaCl/NaHCO3-stimulated ATPase were compared; their possible involvement in secretion in small intestine epithelium is discussed.