Similarities and differences between organic cation inhibition of the Na, K-ATPase and PMCA

The impacts of three classes of organic cations on the inhibition of the plasma membrane Ca pump were determined and compared to inhibition of the Na pump. It was found that the monovalent cation quarternary amines are unable to form hydrogen bonds, and that the positive charge is localized at the center of the compound sterically hindered from direct contact with amino acid side chains.