How Hormones Regulate Blood Sugar Levels

To maintain a constant blood-glucose level, your body relies on two hormones produced in the pancreas that have opposite actions: insulin and glucagon.

Insulin and glucagon have opposite effects on liver and other tissues for controlling blood-glucose level.

Glucagon is a hormone produced by the pancreas to regulate blood sugar levels. It works with insulin to help achieve a balanced sugar level in the bloodstream by prompting the liver to release more glucose when blood sugar levels are low. This occurs usually after exercise and in between meals.

Insulin is made and secreted by the beta cells of the pancreatic islets, small islands of endocrine cells in the pancreas. Insulin is a protein hormone that contains 51 amino acids. Insulin is required by almost all of the body's cells, but its major targets are liver cells, fat cells and muscle cells. For these cells, insulin does the following:

• Stimulates liver and muscle cells to store glucose in glycogen
• Stimulates fat cells to form fats from fatty acids and glycerol
• Stimulates liver and muscle cells to make proteins from amino acids
• Inhibits the liver and kidney cells from making glucose from intermediate compounds of metabolic pathways (gluconeogenesis)

As such, insulin stores nutrients right after a meal by reducing the concentrations of glucose, fatty acids and amino acids in the bloodstream. Insulin is only released when blood sugar levels are high.


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