|Anatomical terms of microanatomy|
Alpha cells (α-cells) are endocrine cells in the pancreatic islets of the pancreas. They make up to 20% of the human islet cells 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 into glucose. This process is called glycogenolysis. In rodents, alpha cells are located in the periphery of the islets, however in humans, the islet architecture is generally less organized and alpha cells are frequently observed inside the islets as well. When viewed from an electron microscope, alpha cells can be identified by their characteristic granules with a large dense core and a small white halo.
- Kerr, J B (2000). Atlas of functional histology. Uk: Mosby. p. 309. ISBN 0-7234-3072-1.
- Stanojevic, Violeta; Habener, Joel F. (2015-10-08). "Evolving Function and Potential of Pancreatic Alpha Cells". Best Practice & Research. Clinical Endocrinology & Metabolism. 29 (6): 859–871. doi:10.1016/j.beem.2015.10.002. ISSN 1521-690X. PMC 4690008. PMID 26696515.
- Quesada, Ivan; Tudurí, Eva; Ripoll, Cristina; Nadal, Ángel (2008-10-01). "Physiology of the pancreatic α-cell and glucagon secretion: role in glucose homeostasis and diabetes". Journal of Endocrinology. 199 (1): 5–19. doi:10.1677/JOE-08-0290. ISSN 0022-0795. PMID 18669612.