Biphasic Insulins: An insulin preparation that is designed to provide immediate and long term glycemic control in a single dosage. Biphasic insulin typically contains a mixture of REGULAR INSULIN or SHORT-ACTING INSULIN combined with a LONG-ACTING INSULIN.Insulin Aspart: Insulin that has been modified to contain an ASPARTIC ACID instead of a PROLINE at position 38 of the B-chain.Insulin, Isophane: An intermediate-acting INSULIN preparation with onset time of 2 hours and duration of 24 hours. It is produced by crystallizing ZINC-insulin-PROTAMINES at neutral pH 7. Thus it is called neutral protamine Hagedorn for inventor Hans Christian Hagedorn.Insulin: A 51-amino acid pancreatic hormone that plays a major role in the regulation of glucose metabolism, directly by suppressing endogenous glucose production (GLYCOGENOLYSIS; GLUCONEOGENESIS) and indirectly by suppressing GLUCAGON secretion and LIPOLYSIS. Native insulin is a globular protein comprised of a zinc-coordinated hexamer. Each insulin monomer containing two chains, A (21 residues) and B (30 residues), linked by two disulfide bonds. Insulin is used as a drug to control insulin-dependent diabetes mellitus (DIABETES MELLITUS, TYPE 1).Hypoglycemic Agents: Substances which lower blood glucose levels.Glucose: A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement.Islets of Langerhans: Irregular microscopic structures consisting of cords of endocrine cells that are scattered throughout the PANCREAS among the exocrine acini. Each islet is surrounded by connective tissue fibers and penetrated by a network of capillaries. There are four major cell types. The most abundant beta cells (50-80%) secrete INSULIN. Alpha cells (5-20%) secrete GLUCAGON. PP cells (10-35%) secrete PANCREATIC POLYPEPTIDE. Delta cells (~5%) secrete SOMATOSTATIN.Receptor, Insulin: A cell surface receptor for INSULIN. It comprises a tetramer of two alpha and two beta subunits which are derived from cleavage of a single precursor protein. The receptor contains an intrinsic TYROSINE KINASE domain that is located within the beta subunit. Activation of the receptor by INSULIN results in numerous metabolic changes including increased uptake of GLUCOSE into the liver, muscle, and ADIPOSE TISSUE.Secretory Vesicles: Vesicles derived from the GOLGI APPARATUS containing material to be released at the cell surface.Diabetes Mellitus, Type 2: A subclass of DIABETES MELLITUS that is not INSULIN-responsive or dependent (NIDDM). It is characterized initially by INSULIN RESISTANCE and HYPERINSULINEMIA; and eventually by GLUCOSE INTOLERANCE; HYPERGLYCEMIA; and overt diabetes. Type II diabetes mellitus is no longer considered a disease exclusively found in adults. Patients seldom develop KETOSIS but often exhibit OBESITY.Insulin-Secreting Cells: A type of pancreatic cell representing about 50-80% of the islet cells. Beta cells secrete INSULIN.Exocytosis: Cellular release of material within membrane-limited vesicles by fusion of the vesicles with the CELL MEMBRANE.Hemoglobin A, Glycosylated: Minor hemoglobin components of human erythrocytes designated A1a, A1b, and A1c. Hemoglobin A1c is most important since its sugar moiety is glucose covalently bound to the terminal amino acid of the beta chain. Since normal glycohemoglobin concentrations exclude marked blood glucose fluctuations over the preceding three to four weeks, the concentration of glycosylated hemoglobin A is a more reliable index of the blood sugar average over a long period of time.Insulin Resistance: Diminished effectiveness of INSULIN in lowering blood sugar levels: requiring the use of 200 units or more of insulin per day to prevent HYPERGLYCEMIA or KETOSIS.Drug Administration Schedule: Time schedule for administration of a drug in order to achieve optimum effectiveness and convenience.Insulin Receptor Substrate Proteins: A structurally-related group of signaling proteins that are phosphorylated by the INSULIN RECEPTOR PROTEIN-TYROSINE KINASE. The proteins share in common an N-terminal PHOSPHOLIPID-binding domain, a phosphotyrosine-binding domain that interacts with the phosphorylated INSULIN RECEPTOR, and a C-terminal TYROSINE-rich domain. Upon tyrosine phosphorylation insulin receptor substrate proteins interact with specific SH2 DOMAIN-containing proteins that are involved in insulin receptor signaling.Insulin, Long-Acting: Insulin formulations that contain substances that retard absorption thus extending the time period of action.Insulin Antibodies: Antibodies specific to INSULIN.Insulin Antagonists: Compounds which inhibit or antagonize the biosynthesis or action of insulin.