Tags: Anatomical Structure.
Alpha cells are endocrine cells in the islets of Langerhans of the pancreas. They make up 33-46% of the human islet cells[citation needed] and are responsible for synthesizing and secreting the peptide hormone glucagon which elevates the glucose levels in the blood.To elevate glucose levels glucagon binds to receptors on hepatocytes (liver cells) and some other cells (e.g. kidney cells). This activates an enzyme glycogen phosphorylase inside the hepatocyte to hydrolyse glycogen to glucose.