Studies on Phospholipase A in Pancreatitis

Part I. Significance of Phospholipase A in Duodenal Juice

Abstract

Phospholipase A activities were determined by means of modified thin layer chromatographic method. The exocrine secretory behavior of phospholipase A and its interrelation to various lipid compositions in duodenal juice with pancreozymin-secretin test were discussed.
When the lipid composition of duodenal juice immediately after aspiration from the duodenal cavity using the pancreozymin-secretin test was compared with those of gallbladder bile, no significant change was observed in the level of neutral fat, cholesterol, total phospholipid, cephalin and sphingomyelin, while the free fatty acid and lysolecithin were increased, and lecithin was decreased. When duodenal juice was incubated at 37°C, total phospholipid, lecithin and free cholesterol decreased and increases in lysolecithin, free fatty acid and esterified cholesterol were observed. Phospholipase A which is secreted from the pancreas, changes the lecithin of the gallbladder bile into lysolecithin and free fatty acid, and this enzymatic reaction was activated in the presence of various bile salts, lysolecithin and albumin, but inhibited by adding neutral fat and free fatty acid.
Phospholipase A showed a significant positive correlation to amylase in controls, the patients with chronic non-calcified pancreatitis and pancreatic calcification. The secretory patterns also showed similar trends. Compared to phospholipase A, amylase was more strongly disturbed in the patients with chronic pancreatitis.