Pancreas anatomy and functions Custom Search
The pancreas is both an exocrine gland and an endocrine gland. It is situated across the abdomen behind the stomach. The right end of this organ is wider and is called head. It is situated in the curve formed by the first part of small intestine called duodenum. The left end is tapering and is called the tail. It extends up to the spleen. It is 12.5 to 15 cm long and weighs between 60 to 100 gm. As an exocrine gland it secretes digestive juices which contain enzymes for the digestion of proteins, fats and carbohydrates. This juice is carried by the pancreatic duct (a tube like structure) which opens into the small intestine along with common bile duct carrying bile from the liver.
Under light microscope it is found to have circularly arranged groups of cells called acini. The cells of the acini secrete the enzymes necessary for digestion. There are some special groups of cells called islets of Langerhans The islets are situated in between the acini.
The Islet cells are responsible for the endocrine function of the organ. They contain four types of cells-alpha,beta,delta and PP (Pancreatic polypeptide) cells. The alpha cells secrete a hormone called glucagon, which increases the level of blood sugar. Its level goes up when the blood sugar level comes down and it acts on the liver cells to release glucose which is stored as glycogen. The beta cells secrete a hormone called insulin which is necessary for the utilization of blood glucose by cells and reducing the level of blood glucose. Deficiency of insulin results in diabetes mellitus. The delta cells secrete a hormone called somatostatin. This is an inhibitory hormone which decreases the secretion of several hormones like growth hormone and insulin. Nature has put in checks and balances at every level. The PP cells secrete a hormone called pancreatic polypeptide. Its exact biological role is unclear. Its level increases after eating protein rich food and when the blood sugar level goes down. Protect your pancreas: Alcohol is known to cause damage to this organ. Custom Search
Page last reviewed on 2nd January 2010
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