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How does somatostatin affect growth hormone, insulin, and glucagon secretion?

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Hormone Many important physiological functions of vertebrates are controlled by steroid hormones.

Somatostatin acts primarily as an inhibitory hormone that regulates various physiological processes by suppressing the secretion of other key hormones.12

Regarding the specific hormones mentioned:

Growth Hormone: Somatostatin was originally identified for its ability to inhibit the release of growth hormone from the pituitary gland.1
Insulin and Glucagon: In the pancreas, somatostatin is produced by delta cells within the islets of Langerhans. From this location, it acts to block the secretion of both insulin and glucagon from adjacent cells.1

By inhibiting these hormones, somatostatin helps control the flow of nutrients, such as glucose, amino acids, and fatty acids, into and out of the circulation. Additionally, it serves as an inhibitory modulator in the gastrointestinal tract, where it suppresses the release of several other hormones, including gastrin.12