Insulin is a key inhibitor of glucagon secretion from pancreatic alpha cells.
Here's a breakdown of factors influencing glucagon inhibition:
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Insulin: Insulin, released by pancreatic beta cells, directly and indirectly inhibits glucagon secretion from alpha cells. This is sometimes referred to as a "glucagonostatic effect." The impaired insulin secretion or action, such as in Type 1 Diabetes (IDDM), can lead to excessive glucagon secretion because this inhibitory influence is reduced.
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Somatostatin: This hormone, secreted by delta cells in the pancreas and other areas of the body, inhibits the release of both insulin and glucagon.
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Glucose: While low glucose levels stimulate glucagon release, high glucose levels, in conjunction with insulin, will suppress glucagon secretion.
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GLP-1 (Glucagon-like peptide-1): GLP-1, an incretin hormone released from the gut in response to food intake, stimulates insulin secretion and also inhibits glucagon secretion.
Summary: The primary inhibitor of glucagon is insulin, but other factors like somatostatin, high glucose levels (indirectly), and GLP-1 also play a role in regulating its secretion. Dysregulation of insulin secretion or action significantly impacts glucagon levels.
