Effects of p-Chloromercuribenzene Sulfonic Acid on Na and Cl Transport by Isolated Gastric Mucosa 1

Summary The effects of the sulfhydryl reactive agent p-chloromercuribenzene sulfonic acid (pCMBS) were measured on isotopic Na and Cl fluxes across isolated fundic and antral mucosa. pCMBS inhibits active Na and Cl transport by both fundic and antral mucosa. Addition of p-chloromercuri-benzoate bound to aminoethyl-dextran (with a mol wt of approximately 10,000) (pCMB-AED) decreases H secretion as well as net Na and Cl transport. Since the effects of a presumably impermeable chloromercuribenzene compound (pCMB-AED) are qualitatively similar to those of a free chloromercuribenzene compound (pCMBS), the active transport effects of pCMBS appear to be due primarily to the oxidation of superficially located thiol groups.