H+ back diffusion and peptic activity related to ulcerogenesis following thermal injury.

This investigation was undertaken to study the effects of cutaneous burn on the integrity of the gastric mucosal barrier (GMB). H+ back diffusion and peptic activity of gastric aspirate were determined in burned and shamburned rats. Twenty-four hours after a 30 percent body surface contact burn (Brevital anesthesia) and a 48-hour fast with saline and ten percent dextrose ad libitim gastric secretions were collected for two hours following pyloric ligation under urethan anesthesia. Studied were: basal secretion, histamine stimulation, glycine instillation, saline instillation, and a combined glycine instillation with histamine augmentation. Significant reductions in acid secretion occurred in burned rats unless the secretion was stimulated by histamine and/or glycine. Following stimulation, acid values in the burned rats exceeded those of unburned rats. GMB disruption, as determined by glycine trapping, was not an apparent pathogenetic mechanism of gastric erosion in 24-hour postburn rats. Peptic activity was elevated in burned rats with mucosal erosion, suggesting a contributory role for this proteolytic enzyme.