Isolation and characterization of rat pancreatic somatostatin.

A peptide representing the major form of somatostatin-like immunoreactivity was isolated from 600 rat pancreata by using anti-somatostatin affinity chromatography, gel permeation chromatography and reverse-phase high-performance liquid chromatography (HPLC). The isolated peptide elutes with the same retention time as synthetic somatostatin-14 in isocratic HPLC and its amino acid composition is in agreement with that of the tetradecapeptide. We propose that the structure of the major rat pancreatic somatostatin is identical to that of somatostatin-14 characterized in other species.