NH2-terminal of gastrin-17 in duodenal ulcer disease: identification of progastrin-17.

Serum gastrin concentrations were measured using antisera with specificity for the carboxyl and amino terminus of gastrin-17 in 50 healthy subjects and 18 patients with active duodenal ulcer disease (DU). The amino terminal of gastrin-17 immunoreactivity was significantly higher in DU patients than in healthy subjects. NH2-terminus of gastrin-17 immunopurified material from serum of DU patients was subjected to Sephadex G50 column chromatography and eluates were monitored by an additional antiserum EG10 that recognizes COOH-terminally extended gastrin. Besides the NH2 terminal tridecapeptide of gastrin-17, COOH-terminally extended progastrin was found. This may reflect abnormal processing of gastrin in patients with active duodenal ulcer disease.