Pepsinogen Group I radioimmunoassay and total serum pepsinogen colorimetric determination: a comparative study in normal subjects and in peptic ulcer patients.

Pepsinogens, proteolytic enzymes produced by peptic cells of the stomach and discharged into the gastric lumen as well as into the blood have been divided into two groups: PG-I, originating from chief cells, and PG-II, mainly from antrum peptic cells. Both total serum pepsinogen (s-Pg) and PG-I have been separately reported as being significantly increased in gastric (GU) and duodenal ulcer (DU) patients and related to maximal acid output. In order to ascertain the relationship between s-Pg measured by means of the colorimetric Uete method, and PG-I determined by RIA method, these were assayed in 72 control subjects, 35 GU and 95 DU patients. s-Pg was found to be significantly increased both in GU and DU patients in comparison with control subjects. Likewise PG-I was significantly enhanced in GU and DU patients as compared with controls. A significant direct correlation between s-Pg and PG-I was found in all the subjects studied (r = 0.732).