title: Luminal alkalinization in the intestine of the goby.
abstract: The rate of luminal alkalinization in vitro by Gillichthys mirabilis posterior intestine as measured by a manual pH stat technique was 0.70 +/- 0.05 mu Equiv/cm2 h; acidification of the mucosal medium was never observed. The rate of HCO-3 secretion (JHCO3) was reduced by ouabain, serosally-applied DIDS, removal of serosal HCO3- and replacement of media Cl- with gluconate. HCO3- secretion was enhanced by replacement of Cl- with isethionate and unaffected by mucosal DIDS, furosemide or acetazolamide. JHCO3 was reduced at mucosal pH above or below 7.5. These results support active HCO3- secretion via a Cl-/HCO3- exchange mechanism on the basolateral membrane and a conductive exit pathway for HCO-3, H+ or OH- on the apical membrane.
mesh_terms: D017878:4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid; D012856:4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D000086:Acetazolamide / Q000494:pharmacology; D000818:Animals; D001639:Bicarbonates / Q000378:metabolism; D002712:Chlorides / Q000378:metabolism; D005260:Female; D005399:Fishes / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007413:Intestinal Mucosa / Q000378:metabolism*; D007422:Intestines / Q000187:drug effects; D008297:Male; D010042:Ouabain / Q000494:pharmacology
chemical_list: D001639:Bicarbonates; D002712:Chlorides; D012856:4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic Acid; D010042:Ouabain; D000086:Acetazolamide; D017878:4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid