Where are Pancreatic islets located?

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.

There are about 1 million islets distributed in the form of density routes throughout the pancreas of a healthy adult human, each of which measures an average of about 0.2 mm in diameter. Each is separated from the surrounding pancreatic tissue by a thin fibrous connective tissue capsule which is continuous with the fibrous connective tissue that is interwoven throughout the rest of the pancreas.