Effects of Luminal ATPase Inhibitors on Electrogenic Ion Transport in Rat Distal Colon1

VO43− inhibits cAMP-stimulated Cl− secretion in rat distal colon at a site distal to cAMP generation without altering intestinal permeability. Ouabain-sensitive luminal K+-ATPases do not seem to contribute to forskolin-stimulated electrogenic ion transport. These findings may suggest new therapeutic targets for secretory diarrhea.