The Pancreas
The pancreas is an elongated gland that lies posterior to the stomach. It is a very active organ, composed of both endocrine and exocrine tissue. Its exocrine function is due to the digestive enzymes that the pancreas secretes into the common bile duct and then into the small intestines. The islet of Langerhans are the hormone producing cells found in the pancreas. The islets of Langerhans secrete four hormones with the first two listed (in bold) being the major two hormones:
1) Insulin (a hormone secreted in response to increased levels of glucose in the blood)…secreted by the beta cells and
2) Glucagon (a hormone secreted in response to decreases level of glucose in the blood) – secreted by the alpha cells stimulates glycogenolysis
3) Somatostatin, produced by the delta cells, maintains constant levels of blood sugar by inhibiting the release of insulin and glucagon; helps to regulate.
4) Pancreatic peptide is produced by the gamma cells to control exocrine secretions from pancreas; helps to regulate.
So remember:
INSULIN
•DECREASES BLOOD GLUCOSE LEVELS by moving glucose INTO cells
GLUCAGON
•INCREASES BLOOD GLUCOSE LEVELS by causing liver to release stored glycogen