The NH₂-Terminal Tridecapeptide Fragment of Gastrin-17 in Serum from Duodenal Ulcer Patients

Abstract

The concentration of gastrin in serum from 47 fasting patients with duodenal ulcer was measured with two radioimmunoassays, one specific for the COOH- and the other specific for NH₂-terminal sequence of gastrin-17. The COOH-terminal assay measured 13 ± 2 pmol and the NH₂-terminal 42 ± 7 pmol-equivalent gastrin-17 per litre (mean ± S.E.M.). This result, corroborated by gel chromatography, shows that an NH₂-terminal fragment of gastrin-17, presumably the tridecapeptide, circulates in concentrations higher than those of the four known gastrin components. The abundance of NH₂-terminal fragment in serum suggests that the complementary COOH-terminal tetrapeptide fragment of gastrin-17 is also produced in large quantities.

Key-words:

• Duodenal ulcer
• gastrin
• radioimmunoassay