Gastric glycoproteins in chronic peptic ulcer.

The output and concentration of gastric glycoproteins in gastric juice from patients with chronic duodenal and gastric ulcer and from controls, have been determined in the basal state and following pentagastrin stimulation. Patients with gastric ulcer had a significantly higher basal glycoprotein output, basal glycoprotein concentration and stimulated glycoprotein concentration than patients with duodenal ulcer or controls. The basal and stimulated glycoprotein output in gastric juice from patients with duodenal ulcer and controls was independent of ABO blood group and secretor status. The carbohydrate composition of the gastric glycoproteins has also been determined in the basal state, and following stimulation of gastric juice by pentagastrin, which did not influence the carbohydrate composition of the molecules. The principal carbohydrate components were galactose, N-acetylglucosamine, fucose, N-acetylgalactosamine, and sialic acid. Small amounts of mannose and glucose were detected in some gastric glycoprotein samples. The carbohydrate composition of the glycoproteins varied according to the ABO blood group and secretor status of the individual. Glycoproteins form stimulated gastric juice from non-secretors of groups A and O had a higher sialic acid content than glycoproteins from secretors of the same blood groups. There were no significant differences in the carbohydrate composition of glycoproteins from patients with chronic gastric and duodenal ulcer compared with gastric glycoproteins from control subjects of the same blood group and secretor status.