The endocrine system has several organs, and each has specific tasks within the body. The messages to carry out these tasks are related to the hormones they release.
The pancreas is largely responsible for maintaining blood sugar (glucose) levels. The normal clinical range of blood glucose levels is 70 to 150 mg/dL (milligrams per deciliter). The pancreas can measure blood sugar and if it is high or low, the pancreas releases a hormone to correct the level. Blood glucose must be maintained at a certain level for cells to neither gain or lose water. Glucose is also vital for cellular respiration to get energy to make sufficient adenosine triphosphate (ATP) to carry out their daily activities.
The pancreas is located near and partially behind the stomach. The endocrine tissue of the pancreas consists of specialized hormone-producing cells called the islets of Langerhans. More than 98% of the pancreas consists of exocrine cells (glands and ducts). These cells secrete digestive enzymes into the gastrointestinal tract.
FUNCTION The islets of Langerhans produce insulin (produced by beta cells) and glucagon (produced by alpha cells). Both play a role in proper metabolism of sugars and starches in the body. Insulin promotes the movement of glucose (sugar) and other nutrients out of the blood and into cells. When blood glucose rises, insulin, released from the beta islet cells causes glucose to enter body cells to be used for energy. Also, it sometimes stimulates conversion of glucose to glycogen (a starch-storage form of sugar) in the liver. Another pancreatic hormone, glucagon, promotes the movement of glucose into the blood when glucose levels are below normal. It causes the breakdown of stored liver glycogen to glucose, so that the sugar content of blood leaving the liver rises.
References:
1. Image credit: University of Colorado at Boulder
2. The Language of Medicine by Davi-Ellen Chabner
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