Some metabolic and biochemical alterations during the development of stress ulcers in rats forced to swim

Swimming of the rats in the water below body temperature (23 degrees C) for a period of 5 hours resulted in a number of acute haemorrhagic lesions, principally erosions, in the glandular part of the stomach. The objective of this study was to establish the possible roles of some hormonal, biochemical and metabolic factors in the pathogenesis of stress ulcer produced in rats forced to swim. It was found that (i) prior ligation of the pylorus caused a considerable decrease of both the incidence and the severity of the ulcers resulting from the swim-stress, (ii) a significant decrease of the gastric secretion and rectal temperature resulted during the swim-stress condition, (iii) metabolic acidosis developed during the forced swimming period, (iv) considerable increases of the plasma corticosterone and blood glucose concentration also developed, (v) the gastric mucosal level of cAMP also increased, and (vi) a prior period of starvation increased the incidence and severity of the acute ulcers resulting from the swim-stress. It was concluded that various humoral, biochemical and metabolic factors play important roles in the development of stress ulceration in rats forced to swim.