Role of pepsin in species differences in erosive gastritis.

This controlled study shows that the rabbit is more vulnerable to erosive gastritis after stress of operation, weight loss, and hypersecretion or acute ischemia than is the cat. Rabbit gastric juice also produces more erosions in the Shay rat preparation after four hours than does cat gastric juice (P less than .05). In vitro, rabbit pepsin has 1.5 times greater specific activity and possesses other kinetic differences. The deleterious effect of these qualitative differences on gastric mucosa may also be augmented by quantitative differences. Hypersecretion of pepsin has been reported once the mucosa is damaged. We conclude that demonstration of species-related differences in pepsin activity helps to explain an apparent discrepancy noted by others--namely, why the rabbit is so much more susceptible to stress-produced erosions than the cat or other experimental animals.