A change in the internal affinity of LK goat red-cell sodium pumps induced by high pH.

The K inhibition of ouabain-sensitive ATPase activity of LK goat red cell membranes is greatly reduced at high pH. This effect is reversible, and specific, since the apparent affinities for ATP, ouabain or external K do not alter. Anti-L-treated membranes show a similar alkali-induced affinity change, but have a lower pH optimum.