Development of pancreatic glucagon-specific radioimmunoassay with use of synthetic human glucagon (19-29) as immunogen.

Recent reports" have described successful production of pancreatic glucagon-specific antisera with the C-terminal tryptic fragment of porcine glucagon, glucagon (19-29), as immunogen. One of the antisera, OAL-123, was efficiently used for development of a radioimmunoassay as a tool for measuring pancreatic glucagon in biologic fluids and tissue extracts2),4). Trypsin-catalyzed digestion of porcine glucagon, however, resulted in the formation of a mixture of products and extensive purification was required for preparation of the homogeneous glucagon (19-29) as immunogen1). Alternatively, we have attempted to synthesize undecapeptide corresponding to the amino acid sequence of glucagon (19-29) 5). The undecapeptide, H-AIaGln-Asp-Phe-Val-Gln-Trp-Leu-Met-Asn-ThrOH, thus obtained in high yield, was proved to be homogenous and has been used for production of the C-terminal specific glucagon antisera. This communication provides evaluation of a glucagon radioimmunoassay with use of antiserum raised against synthetic undecapeptide corresponding to the 19-29 sequence of human glucagon. 1. Materials and Methods