H+ Disposal by Rabbit Gastric Mucosal Surface Cells

摘要: Exposure of isolated gastric mucosal surface cells to NH4+ results in acidification as determined by a fluorescent dye technique using acridine orange. The resulting intracellular pH gradient is maintained when are suspended either buffered HCO3- free Ringer's or choline chloride solution. Cells Na+ -containing but K+-free solution exhibit dissipation the proton gradient. When added Na+, K+ -free solution, rapidly dissipates with half-maximal response occurring at 56 mM Na'. effect amiloride sensitive inhibition 38 µM concentration 50 mM. does not cause and neither ouabain nor valinomycin have an effect. Yet, has modulating influence on Na+/H+ exchange cells. addition acidloaded resuspended decreases ability subsequent evoke dissipation. data suggest that Na'IH+ appears be least one mechanism whereby could protect themselves against diffusing acid. This ion unrelated adenosine triphosphatase activity, affected external concentration.