Epidermal Growth Factor Inhibits Cysteamine-Induced Duodenal Ulcers in Rats

Abstract
We examined the pathogenesis of cysteamine-induced duodenal ulcers in rats, especially with reference to epidermal growth factor (EGF). Control, cysteamine (400 mg/kg, s.c.), cysteamine + EGF (20 micrograms/kg/day, i.p.) submandibular resection (SMR), SMR + cysteamine, and SMR + cysteamine + EGF groups were examined for duodenal ulceration. With submandibular resectioning, endogenous EGF decreased, and with the administration of EGF (i.p.), endogenous EGF increased. In the SMR + cysteamine group, serum gastrin increased and the intragastric pH decreased remarkably compared to in the normal control group. The administration of exogenous EGF suppressed this change. Mucosal blood flow, the potential difference and hexosamine, as defensive factors, decreased markedly in the SMR + cysteamine group, but the administration of exogenous EGF reversed these changes. These results suggested that a decrease in EGF is involved in the pathogenesis of cysteamine-induced duodenal ulcers in rats.