The pancreas produces secretions necessary for you to digest food. The enzymes in these secretions allow your body to digest protein, fat and starch from your food. The enzymes are produced in the acinar cells which make up most of the pancreas. From the acinar cells the enzymes flow down various channels into the pancreatic duct and then out into the duodenum. The secretions are alkaline to balance the acidic juices and partially digested food coming into the duodenum from the stomach. A small proportion per cent of the pancreas is made up of other types of cells called islets of Langerhans.
These cells sit in tiny groups, like small islands, scattered throughout the tissue of the pancreas. The islets of Langerhans contain alpha cells which secrete glucagon and beta cells which secrete insulin. Insulin and glucagon are hormones that work to regulate the level of sugar glucose in the body to keep it within a healthy range.
Unlike the acinar cells, the islets of Langerhans do not have ducts and secrete insulin and glucagon directly into the bloodstream. Insulin is released from the beta cells in your pancreas in response to rising glucose in your bloodstream. The pancreas detects this rise in blood glucose and starts to secrete insulin. Insulin works by improving the uptake of glucose from the blood across cell membranes and into the cells of the body, and so takes glucose out of the bloodstream.
Once in the cells, the glucose is used as the energy to fuel the cells doing their different jobs or is stored in the liver or muscle cells as glycogen. This results in the glucose level of the blood dropping, which then triggers the pancreas to switch off the release of insulin. Glucagon has an opposite antagonistic effect to insulin. When your blood glucose level falls, for example during exercise when your muscles are using glucose for fuel, your pancreas detects the drop in blood glucose.
This prompts the pancreas to slow down the secretion of insulin, but increase the output of glucagon. The role of glucagon is to break down glycogen the stored form of glucose in the liver. Then the liver releases glucose into the bloodstream. This results in a rise in the blood glucose level to bring it back to a healthy level, which in turn signals the pancreas to switch off glucagon release. The control of blood glucose levels operates by what is known as a negative feedback mechanism.
Here is a summary of the 2 control loops. Diabetes Australia. June Diabetes UK. This energy is needed for metabolism , exercise and, in particular, to fuel the parts of the brain that 'run' on glucose.
This makes sure that the body doesn't starve between meals. The most important hormone that the pancreas produces is insulin. Insulin is released by the 'beta cells' in the islets of Langerhans in response to food.
Its role is to lower glucose levels in the bloodstream and promote the storage of glucose in fat, muscle, liver and other body tissues. This has the opposite effect to insulin, by helping release energy into the bloodstream from where it is stored, thus raising blood sugar levels. Therefore, glucagon and insulin work in tandem to control the balance of glucose in the bloodstream. Other hormones produced by the pancreas include pancreatic polypeptide and somatostatin. They are believed to play a part in regulating and fine-tuning the insulin and glucagon-producing cells.
Type 1 diabetes mellitus is caused when the body's immune system attacks its own cells in the islets of Langerhans, meaning that these cells cannot produce insulin. Type 2 diabetes mellitus is a metabolic disorder where the body is no longer able to produce or respond to insulin.
Some women also get diabetes temporarily when they are pregnant. This is called gestational diabetes. There are other rarer forms of diabetes, some of which are inherited. In addition, people will get diabetes if their pancreas is taken away surgically or damaged for instance by severe pancreatitis.
Very rarely, patients develop growths tumours of the cells that make up the islets of Langerhans. These may be benign tumours, where a particular kind of cell multiplies and makes large quantities of its hormone whether it is needed or not. Feb 14, The pancreas secretes insulin. Explanation: The pancreas is a gland and its endocrine function is to produce insulin, to lower blood sugar, and glucagon, to raise blood sugar. Related questions Where are hormones made?
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