Metabolic base production and mucosal vulnerability during acid inhibition in a mammalian stomach in vitro

Dig Dis Sci. 1996 May;41(5):964-71. doi: 10.1007/BF02091538.

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.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acid-Base Equilibrium* / drug effects
  • Adenosine Triphosphatases / antagonists & inhibitors
  • Animals
  • Bicarbonates / metabolism
  • Carbon Dioxide / metabolism
  • Enzyme Inhibitors / pharmacology
  • Female
  • Gastric Acid / metabolism*
  • Gastric Mucosa / drug effects
  • Gastric Mucosa / metabolism*
  • Gastric Mucosa / pathology
  • Hydrogen-Ion Concentration
  • Imidazoles / pharmacology
  • In Vitro Techniques
  • Mice
  • Serous Membrane / drug effects
  • Serous Membrane / metabolism
  • Serous Membrane / pathology

Substances

  • Bicarbonates
  • Enzyme Inhibitors
  • Imidazoles
  • Sch 28080
  • Carbon Dioxide
  • Adenosine Triphosphatases