≥25 USP units/mg (HPLC), powder

Biochem/physiol Actions

Two-chain polypeptide hormone produced by the β-cells of pancreatic islets. Its molecular weight is ~5800 Da. The α and β chains are joined by two interchain disulfide bonds. The α chain contains an intrachain disulfide bond. Insulin regulates the cellular uptake, utilization, and storage of glucose, amino acids, and fatty acids and inhibits the breakdown of glycogen, protein, and fat.