Influence of exocrine and endocrine pancreatic function on intestinal brush border enzymatic activities

Abstract

Digestive enzymatic activities (disaccharidases, alkaline phosphatase, peptide hydrolases) were determined in the mucosa of 14 patients with chronic pancreatitis. All had an abnormal secretin pancreozymin test. Four patients had insulin dependent diabetes mellitus, 4 a pathological glucose tolerance test. Nine patients had steatorrhoea. Maltase, sucrase, and alkaline phosphatase activity was significantly elevated in patients with exocrine pancreatic insufficiency, whereas those of lactase, trehalase, and peptide hydrolase were normal. Patients with steatorrhoea had higher maltase and sucrase activity than those without steatorrhoea, whereas decreased glucose tolerance had no effect on brush border enzymatic activity. It is suggested that decreased exocrine rather than decreased endocrine pancreatic function is responsible for the increase in intestinal disaccharidase and alkaline phosphatase activity, possibly by the influence of pancreatic enzymes on the turnover of brush border enzymes from the luminal side of the mucosal membrane or by direct hormonal stimulation through cholecystokinin.