Insulin Insulin Insulin (from Latin "insula", island) is a peptide hormone produced by beta cells of the pancreatic islets; it is considered to be the main anabolic hormone of the body. It regulates the metabolism of carbohydrates, fats and protein by promoting the absorption of carbohydrates, especially glucose from the blood into liver, fat and skeletal muscle cells. In these tissues the absorbed glucose is converted into either glycogen via glycogenesis or fats (triglycerides) via lipogenesis, or, in the case of the liver, into both. Glucose production and secretion by the liver is strongly inhibited by high concentrations of insulin in
NPH insulin action, which is the primary reason NPH remains on the market today, because manufacturers sell a variety of premixed insulin formulations. Eventually all animal insulins made by Novo Nordisk were replaced by synthetic, recombinant 'human' insulin. Synthetic 'human' insulin is also complexed with protamine to form NPH. It has an intermediate duration of action, meaning longer than that of regular and rapid-acting insulin, and shorter than long acting insulins (ultralente, glargine or detemir). NPH insulin may be combined with faster acting insulin to allow more accurate dosing and better blood sugar level control. When administered this way, the two insulin