Insulin Overview

Insulin Overview

Source

  • Secreted by B-cells (Beta-cells) of the islets of Langerhans (in the pancreas).

Functions

  • Lowers blood glucose.

  • Modulates metabolic disposition of (FAC):

    • Fats

    • Amino acids

    • Carbohydrates

Secretion Companions

  • Inactive C-peptide is secreted alongside insulin.

Clinical Relevance of C-peptide

  • Provides an index of insulin secretion:

    • Low or absent in type 1 diabetes.

    • High in insulinoma (tumor causing hypoglycemia).

Differentiation

  • C-peptide vs. C-reactive peptide (CRP):

    • CRP: Acute phase protein from the liver, non-specific index of inflammation.

Insulin Injection Hypoglycemia

  • C-peptide concentration is not elevated in hypoglycemia due to insulin injection.