Effects of 2-[4-(2-imidazo[1,2-a]pyridyl)phenyl] propionic acid (Y-9213) on in vivo release of lysosomal enzymes from rat polymorphonuclear leukocytes during phagocytosis of particles.

Intraperitoneal administration of carrageenin-zymosan suspension into rats induced an increment of the free activity and its ratio of aryl sulfatase in the exudate and such was accompanied by protein exudation and polymorphonuclear leukocyte emigration. Each test solution was orally administered twice, 1 hr before and 2 hr after, or once 2 hr after injection of the irritant. The peritoneal fluid was withdrawn 5 hr after the injection. 2-[4-(2-imidazo[1,2-a]pyridyl)phenyl] propionic acid (Y-9213) and other anti-inflammatory drugs tested inhibited the increment of the ratio of the free activity (aryl sulfatase) in the peritoneal fluid at the same dose which showed anti-inflammatory activities such as prevention of protein exudation. These results suggest that Y-9213 inhibits the phagocytic secretion in vivo of lysosomal constituents from leukocytes.