The pancreatic islets or islets of Langerhans are the regions of the pancreas that contain its endocrine (hormone-producing) cells, discovered in 1869 by German pathological anatomist Paul Langerhans. The pancreatic islets constitute 1–2% of the pancreas volume and receive 10–15% of its blood flow. The pancreatic islets are arranged in density routes throughout the human pancreas, and are important in the metabolism of glucose.
A pancreatic islet from a mouse in a typical position, close to a blood vessel; insulin in red, nuclei in blue.
A pancreatic islet, stained.
A pancreatic islet, showing alpha cells
A pancreatic islet, showing beta cells.
Paul Langerhans was a German pathologist, physiologist and biologist, credited with the discovery of the cells that secrete insulin, named after him as the islets of Langerhans.
Paul Langerhans in 1878
Langerhans as a student