Comparative Effects of Aliphatic Alcohols on the Gastric Mucosa

Abstract

Summary

We studied the effects of a series of aliphatic alcohols on the gastric mucosa of Heidenhain pouches in four unanesthetized dogs. Transmucosal potential difference (PD). and the net fluxes of H⁺, Na⁺, and Cl–, were determined in the presence of various concentrations of methanol, ethanol, n-propanol, and t-butanol. Each alcohol caused a decrease in the PD and an increase in the net flux of Na⁺ ion into the lumen of the pouch. On a molar basis, t-butanol = n-propanol > ethanol > methanol in their effects on PD and net Na⁺ flux. Except for t-butanol there was a linear relationship between the ability of the alcohol to alter PD and the oil-water partition coefficient of the alcohol. Low concentrations of ethanol and n-propanol caused a net flux of H⁺ ion into the pouch (secretion). Higher concentrations of these alcohols and all concentrations of methanol and t-butanol caused a net loss of H⁺ ion from the pouch. The net flux of Cl- ion tended to parallel and equal the net flux of cations.

We conclude that (a) there is no optimal carbon-chain length between C-1 and C-4 for the “damaging” effects of alcohol on the mucosa, (b) the degree of “damage” is best correlated with the lipid solubility of the damaging agent, and (c) there is good correlation between the PD changes and the change in net Na⁺ flux but not the change in net H⁺ flux.

The authors thank Dr. Lee Forker for valuable advice and for instructions in the use of the scintillation counter. This work was supported by Grant AM 15886 from the U.S. Public Health Service and Veterans Administration Research Funds. A preliminary report of this study was presented at the Amer.