The Islets of Langerhans are specialized cells of the pancreas. A healthy adult pancreas contains about 1 million islet cells. These cells produce and secrete such hormones as insulin, glucagon and somatostatin into the bloodstream. These hormones help regulate blood sugar levels and energy production.
Diabetes develops when the islet cells cannot make insulin (type 1 diabetes) or cannot produce sufficient amounts of properly-functioning insulin for bodily needs (type 2 diabetes). It is called insulin resistance when the body cannot properly use insulin.
The Pancreas. Johns Hopkins Medicine. Accessed July 11, 2011. http://pathology.jhu.edu/pc/BasicOverview1.php
Pancreatic Diseases. Lab Tests Online. Accessed: July 11, 2011. http://labtestsonline.org/understanding/conditions/pancreatic-diseases/