title: Metabolic base production and mucosal vulnerability during acid inhibition in a mammalian stomach in vitro.
abstract: Acid inhibition increases gastric mucosal susceptibility to damage by luminal acid. This might be due to reduced metabolic CO2 and bicarbonate whereas, during normal acid, secretion cytoprotective CO2/HCO3- production parallels acid production. Metabolic activity and mucosal damage caused by luminal acid perfusion was determined in an in vitro mouse stomach, with and without acid inhibition, and at 0%, 1%, or 5% serosal CO2 supply. Without acid inhibition there was no mucosal damage at any level of serosal CO2/HCO3- supply. Acid inhibition reduced metabolic CO2 production by 29% (P < 0.004) and resulted in microscopic damage to 55% of the mucosal area and perforation in four of five stomachs (P < 0.05). Although, 1% CO2 supply completely replaced the reduction in metabolic CO2, it did not protect against mucosal damage. Overreplacement by 5% serosal CO2/HCO3- was required to prevent damage. There was no correlation between luminal CO2/HCO3- output and mucosal damage. The protection by endogenous or exogenous CO2/HCO3- appears to act intracellularly rather than by intragastric or intercellular neutralization.
authors.affiliation: Department of Gastroenterology, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland.
authors.forename: M
authors.initials: M
authors.lastname: Glauser
authors.forename: P
authors.initials: P
authors.lastname: Bauerfeind
authors.forename: W
authors.initials: W
authors.lastname: Feil
authors.forename: M
authors.initials: M
authors.lastname: Riegler
authors.forename: R
authors.initials: R
authors.lastname: Fraser
authors.forename: A L
authors.initials: AL
authors.lastname: Blum
mesh_terms: D000136:Acid-Base Equilibrium / Q000187:drug effects; D000251:Adenosine Triphosphatases / Q000037:antagonists & inhibitors; D000818:Animals; D001639:Bicarbonates / Q000378:metabolism; D002245:Carbon Dioxide / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005260:Female; D005744:Gastric Acid / Q000378:metabolism*; D005753:Gastric Mucosa / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D006863:Hydrogen-Ion Concentration; D007093:Imidazoles / Q000494:pharmacology; D066298:In Vitro Techniques; D051379:Mice; D012704:Serous Membrane / Q000187:drug effects / Q000378:metabolism / Q000473:pathology
chemical_list: D001639:Bicarbonates; D004791:Enzyme Inhibitors; D007093:Imidazoles; C035235:Sch 28080; D002245:Carbon Dioxide; D000251:Adenosine Triphosphatases