Salicylate effects on proton gradient dissipation by isolated gastric mucosal surface cells.
The effects of salicylate were examined on Na+/H+ exchange by isolated gastric mucosal surface cells loaded with H+ and resuspended in a buffered medium. Choline salicylate (pH 7.4) increases the dissipation of an intracellular proton gradient which was measured using acridine orange. The exchange of extracellular Na+ with intracellular H+ by surface cells not only remains intact but also is enhanced upon exposure to salicylate. This was confirmed by cellular uptake of 22Na and titration of cellular H+ efflux. Salicylate increases Na+/H+ exchange via a pathway predominantly sensitive to amiloride. However, the data also suggest that salicylate dissipates an intracellular proton gradient by an additional mechanism. The latter is independent of extracellular Na+ and not due to a generalized increase in cellular permeability.
D000584:Amiloride / Q000494:pharmacology; D000818:Animals; D001639:Bicarbonates / Q000378:metabolism; D002463:Cell Membrane Permeability; D002478:Cells, Cultured; D005753:Gastric Mucosa / Q000187:drug effects* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007474:Ion Exchange; D011522:Protons; D011817:Rabbits; D012459:Salicylates / Q000494:pharmacology*; D020156:Salicylic Acid; D012964:Sodium / Q000378:metabolism
D001639:Bicarbonates; D011522:Protons; D012459:Salicylates; D000584:Amiloride; D012964:Sodium; D020156:Salicylic Acid