Hormones: Glucagon
Glucagon is secreted to maintain glucose levels in the bloodstream when fasting and to raise very low glucose levels. What is glucagon? Glucagon is a hormone that is involved in controlling blood sugar (glucose) levels. It is secreted into the bloodstream by the alpha cells, found in the islets of Langerhans, in the pancreas. The glucagon-secreting alpha cells surround a core of insulin-secreting beta cells, which reflects the close relationship between the two hormones. Glucagon’s role in the body is to prevent blood glucose levels dropping too low. To do this, it acts on the liver in several ways: It stimulates the conversion of stored glycogen (stored in the liver) to glucose which can be released into the bloodstream. This process is called glycogenolysis. It promotes the production of glucose from amino acid molecules. This process is called gluconeogenesis. It reduces glucose consumption by the liver so that as much glucose as possible can be secreted into the bloodst...