Glucagon and glicentin immunoreactivity are topologically segregated in the alpha granule of the human pancreatic A cell.

Glicentin is a 100-amino acid polypeptide purified from the porcine intestine and containing the immunodeterminants of glucagon. We have previously reported the presence of glicentin immunoreactivity in the glucagon-containing, specific secretory granules (alpha granules) of the pancreatic and gastric A cell. With an improved immunocytochemical probe, the protein A-gold (pAg) technique, we are now able to show that glucagon and glicentin-like material are topologically segregated in the alpha granule of the human pancreatic A cell.