Correlations between changes in indicators of gastric mucosal barrier integrity at time of exposure to "barrier breakers" and extent of hemorrhagic erosions one hour later.

We have examined the effects of seven different "barrier breakers" (including ethanol, aspirin, salicylic acid, isobutyric acid, Na taurocholate, thermal injury, and hyperosmotic glucose) on chambered gastric mucosae of rats in an attempt to identify variations in accepted indicators of mucosal barrier integrity which would accurately predict the extent of subsequent hemorrhagic erosion. When results from all experimental groups were considered, only the initial decrease in transmucosal potential difference (PD) showed significant correlation with final damage (lesion area). When the results were analyzed as separate subgroups, significant correlations were also found between net K+ efflux during the first 10 min after luminal infusion and final lesion area. Only in the subgroup containing ethanol, salicylates, and thermal injury was there a correlation between net loss of luminal H+ (back-diffusion) and lesion area. These results are considered in terms of their implications for the ulcerogenic actions of each group of agents.