Genetically obese (ob/ob) mice are predisposed to gastric stress ulcers.

Genetically obese (ob/ob) mice and lean littermate controls were food deprived and subsequently physically restrained at normal room temperatures. Obese mice became hypothermic and developed gastric stress ulcers. Lean mice maintained normal body temperatures and did not form gastric ulcers. Oxygen consumption was measured during food deprivation and restraint. Obese and lean mice had parallel metabolic responses, with obese animals using significantly less oxygen at all times. The predisposition to formation of gastric ulcers is a new phenotypic expression of the ob/ob genotype. The pathogenesis of this susceptibility appears to be related to a genetic disturbance in heat production.