Serum Platelet-Activating Factor Acetylhydrolase Activity in Rats with Gastric Ulcers Induced by Water-Immersion Stress

Abstract

Platelet-activating factor (PAF) acetylhydrolase is an enzyme which hydrolyzes PAF to yield inactive lysoPAF. This study focused on the influence of water-immersion stress on serum PAF acetylhydrolase activity. The enzyme activity was determined by measurement of [3H]acetate produced from 1-O-alkyl-2-[3H]acetyl-sn-glycero-3-phosphocholine upon precipitation of the complex of the radioactive substrate and albumin with trichloroacetic acid. The onset of water-immersion stress caused the development of gastric lesions associated with a significant increase in serum PAF acetylhydrolase activity. Serum PAF acetylhydrolase may leak into the blood from some tissues in rats with gastric injury induced by water-immersion stress and might control the action of PAF.