Inhibitory effect of a caerulein-like peptide on human gastric secretion.

Abstract A synthetic heptapeptide corresponding to the C-terminal heptapeptide of caerulein but characterized by a nor-leucyl residue replacing the methyonyl residue of caerulein, when given by i.v. infusion (2μg/kg/h), inhibited by 70–80% pentagastrin (4μg/kg/h)-stimulated gastric secretion. The compound which caused no harmful side effects exhibited a rather prolonged effect which was evident even after discontinuing the infusion. This synthetic peptide represents so far the best caerulein analogue acting as competitive inhibitor of pentagastrin-induced secretion.