The antibody is specific to pancreatic glucagon. Glucagon is produced by the alpha-cells of the pancreatic islets. It occurs also in endocrine cells of the gut and in neurons in the brain. Glucagon is a common constituent of endocrine pancreatic tumours and of rectal carcinoids, such tumours may give rise to the so called glucagonoma syndrome. The antigen localization is cytoplasmic.Positive control: Pancreas.