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

In Exp I, 20 adult male genetically obese (ob/ob) mice and 20 lean littermate controls were food deprived and subsequently physically restrained at normal room temperatures. Obese Ss became hypothermic and developed gastric stress ulcers. Lean Ss maintained normal body temperatures and did not form gastric ulcers. In Exp II, 5 male obese and 4 lean littermates were used to test the effects of noradrenaline (NA) during restraint, and 5 obese and 5 lean mice were used to test the effects of NA alone. It was expected that in lean, but not in obese, Ss that NA would induce an increase in O? consumption beyond that induced by initial restraint. O? consumption was measured during food deprivation and restraint. Obese and lean Ss had parallel metabolic responses, with obese Ss using significantly less O? 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. (14 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)