... posterior midgut by measuring the transepithelial voltage ( V te ) and the rate of acid secretion as indicated by the color change of m -cresol purple during intervals of perfusion stop. The lumen-positive V te and reacidification were significantly increased by serotonin (0.2 μmol l −1 ). The V-type H...

...( r 2 =0.72, P =0.001). There were no significant differences in pH between continuous in situ and laboratory serial sample measurements. Together these findings indicate that gastric acid secretion may be continuous in leopard sharks, and that changes in gastric pH may be used to estimate feeding...

... . Under normoxic conditions, the pHi of goldfish hepatocytes was regulated by a Na + /H + exchanger and a Na + -independent Cl – /HCO 3 – exchanger, the latter being activated only after acidification of the cells. Mechanisms of acid secretion appear to be fuelled, at least in part, by lactate formation...

...STEVEN J. YOUMANS; CATHERINE R. BARRY SUMMARY An earlier report indicated that acid secretion in turtle urinary bladder is driven by an unusual vacuolar H + -ATPase and that the ATPase accounts for essentially all acid secreted. These results, however, are difficult to reconcile with the acid...

... extracellular environment of the stomach. * Author for correspondence. H + pump Na + pump glycosylation subunit assembly trafficking acid secretion All cells possess an array of sophisticated membrane-bound enzymatic systems that perform various processes essential for life...