Glucose, or blood sugar, is the body's main source of energy. The pancreas is an organ which contains tiny clusters of tissues called islets of Langerhans. The cells found on the islets produce hormones that regulate the blood sugar levels in the body.
Pancreatic cells
The pancreatic islets have four types of cells that secrete different hormones. Two types of cells control blood sugar levels in the body. "Principles of Anatomy and Physiology" explains that alpha cells constitute about 15 percent of pancreatic islet and secrete glucagon, and beta cells make up about 80 percent of pancreatic islets cells and release insulin.
Glucagon and Insulin
Glucagon is the hormone that increases blood glucose level when it drops below the normal range. Insulin is the hormone that lowers blood sugar level when it is too high.
Control of Sugar Levels
Low blood glucose level stimulates the secretion of glucagon, which acts on liver cells to convert glycogen, or stored energy, to glucose. This leads to a rise in glucose levels. On the other hand, when glucose levels are high, insulin is released from the pancreas and stops the release of glucagon. According to "Rubin's Pathology," insulin blocks the effects of glucagon, enhances the production of glycogen and stops the breakdown of glycogen.
References
- "Principles of Anatomy and Physiology"; Gerard J. Tortora, Bryan Derrickson; 2009
- "Rubin's Pathology: Clinicopathologic Foundations of Medicine"; Raphael Rubin, David Strayer, etal.; 2007
