Alpha cells are endocrine cells in the islets of Langerhans of the pancreas. They make up 15-20% of the cells in the islets. They are responsible for synthesizing and secreting the peptide hormone glucagon, which elevates the glucose levels in the blood. This is done by Glucagon binding to receptors on hepatocytes (liver cells) and other cells (e.g muscle), this activates an enzyme, glycogen phosphorylase, inside the hepatocyte to hydrolyse glycogen to glucose, this process is called glycogenolysis. In rodents alpha-cells are located in the periphery of the islets, in humans the islet architecture is generally less organized and alpha-cells are frequently observed inside the islets as well. In the electron microscope alpha-cells can be identified by their characteristic granules with a large dense core and a small white halo.
Alternative and more common spelling: alpha-cell or α-cell.
See also
External links
|
