In vitro Inhibition of Na + -K + and Mg 2+ ATPases by Mono,Di and Trivalent Cations. ∗

Abstract

Summary

Na⁺-K⁺ ATPase has been found to be strongly inhibited in vitro by addition of silver, vanadium, copper, zinc, cadmium, lead and mercury. Calcium, strontium and barium enhance the dephosphorylation of ATP in the presence of Mg²⁺ dependent ATPase, while exerting an inhibitory effect on the monovalent cation stimulated portion. Cesium acts as an activator of Mg²⁺ ATPase in the system studied.