Insulin

insulin /in·su·lin/ (in´sdbobr-lin)

1. a protein hormone formed from proinsulin in the beta cells of the pancreatic islets of Langerhans. The major fuel-regulating hormone, it is secreted into the blood in response to a rise in concentration of blood glucose or amino acids. Insulin promotes the storage of glucose and the uptake of amino acids, increases protein and lipid synthesis, and inhibits lipolysis and gluconeogenesis.

Insulin. The precursor proinsulin is cleaved internally at two sides (arrows) to yield insulin and C peptide.

2. a preparation of insulin, either of porcine or bovine origin or a recombinant form with sequence the same as or similar to that in humans, used in the treatment of diabetes mellitus; classified as rapid-acting, intermediate-acting, or long-acting on the basis of speed of onset and duration of activity.

3. regular insulin; a rapid-acting, unmodified form of insulin prepared from crystalline bovine or porcine insulin.

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insulin aspart  a rapid-acting analogue of human insulin created by recombinant DNA technology.

buffered insulin human  insulin human buffered with phosphate; used particularly in continuous infusion pumps.

extended insulin zinc suspension  a long-acting insulin consisting of porcine or human insulin in the form of large zinc-insulin crystals.

insulin glargine  an analogue of human insulin produced by recombinant DNA technology, having a slow, steady release over 24 hours.

insulin human  a protein corresponding to insulin elaborated in the human pancreas, derived from pork insulin by enzymatic action or produced synthetically by recombinant DNA techniques; sometimes used specifically to denote a rapid-acting regular insulin preparation of this protein.

isophane insulin suspension  an intermediate-acting insulin consisting of porcine or human insulin reacted with zinc chloride and protamine sulfate.

Lente insulin  insulin zinc suspension.

insulin lispro  a rapid-acting analogue of human insulin synthesized by means of recombinant DNA technology.

NPH insulin  isophane i. suspension.

prompt insulin zinc suspension  a rapid-acting insulin consisting of porcine insulin with zinc chloride added to produce a suspension of amorphous insulin.

regular insulin  insulin (3).

Semilente insulin  prompt insulin zinc suspension.

Ultralente insulin  extended insulin zinc suspension.

insulin zinc suspension  an intermediate-acting insulin consisting of porcine or human insulin with a zinc salt added such that the solid phase of the suspension contains a 7:3 ratio of crystalline to amorphous insulin.

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in·su·lin (ns-ln)

n.

1. A polypeptide hormone that is secreted by the islets of Langerhans, helps regulate the metabolism of carbohydrates and fats, especially the conversion of glucose to glycogen, and promotes protein synthesis and the formation and storage of neutral lipids.

2. Any of various pharmaceutical preparations containing this hormone that are derived from the pancreas of certain animals or produced through genetic engineering and are used parenterally in the medical treatment and management of insulin-dependent diabetes mellitus.

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Insulin

A hormone secreted by the pancreas in response to high blood sugar levels that induces hypoglycemia. Insulin regulates the body's use of glucose and the levels of glucose in the blood by acting to open the cells so that they can intake glucose.

Mentioned in: Diabetes Mellitus, Diabetic Ketoacidosis, Gestational Diabetes, Hypothermia, Insulin Resistance

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insulin (inˑ·s·lin),

n hormone produced by the pancreas that regulates blood glucose levels by stimulating the absorption of sugars into the cells.

Insulin injection sites.

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insulin (antidiabetic hormone) (in´-slin´ an´tēdī´bet´ik),

n a hormone produced by the beta cells of the islets of Langerhans in the pancreas. It promotes a decrease in blood sugar. Its action may be influenced by the pituitary growth hormone, adrenocorticotropic hormone; hormones of the adrenal cortex; epinephrine; glucagon; and thyroid hormone.

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insulin (obtained from beef or pork, or human recombinant technology),

n brand names: Velosulin, Humulin R, Novolin R, Lente Insulin;
drug class: exogenous insulin, antidiabetic;
action: decreases blood glucose; important in regulation of fat and protein metabolism;
uses: ketoacidosis; type 1 and type 2 diabetes mellitus; hyperkalemia; hyperalimentation.

insulin, exogenous

n a type that comes from a source external to a diabetic patient's body, taken to offset the patient's natural deficiency of insulin.

insulin, intermediate-acting,

n a type that is a medium between rapid-acting and long-acting insulins; the onset is not as fast as rapid-acting insulin, but it reaches its peak action over a 4- to 12-hour period.

insulin, Lente

n.pr an intermediate-acting type that reaches its peak action over a 4- to 12-hour period.

insulin, Lispro,

n.pr a rapid-acting type that reaches its peak action in 30 to 90 minutes.

insulin, long-acting,

n a type that has a slow onset but reaches its peak action from 12 to 16 hours after administration.

insulin, NPH,

n a synthetic type used to treat diabetes. Classified as intermediate acting; peak action occurs 4 to 10 hours after administering.

insulin, rapid-acting,

n a synthetic type of insulin used to treat diabetes. Reaches peak action 30 to 90 minutes after administering.

insulin, regular,

n a synthetic type used to treat diabetes. Classified as short acting; peak action occurs 2 to 3 hours after administering.

insulin resistance,

n a complication of diabetes mellitus characterized by a need for more than 200 units of insulin per day to control hyperglycemia and ketosis. The cause is associated with insulin binding by high levels of antibody.

insulin shock,

n See shock, insulin.

insulin, short-acting,

n a synthetic type used to treat diabetes. Reaches peak action 2 to 3 hours after administering. Also called
regular insulin.

insulin, ultralente

n a synthetic type used to treat diabetes. Classified as long acting, with peak action occurring 12 to 16 hours after administering.

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insulin

a double-chain peptide hormone formed from proinsulin in the beta cells of the pancreatic islets of Langerhans. Insulin promotes the storage of glucose and the uptake of amino acids, increases protein and lipid synthesis, and inhibits lipolysis and gluconeogenesis.

The secretion of endogenous insulin is a response of the beta cells to a stimulus. The primary stimulus is glucose; others are amino acids, particularly leucine, and the 'gut hormones', such as secretin, pancreozymin and gastrin. These chemicals play an important role in maintaining normal blood glucose levels by triggering the release of insulin after ingestion of a meal.

Commercially prepared insulin is available in various types, which differ in the speed with which they act and in the duration of their effectiveness. There are three main groups: rapid acting (regular or semilente), intermediate acting (isophane suspension or NPH, zinc suspension or lente), and long acting (protamine zinc suspension or PZI, or ultralente). Mixtures are also marketed.

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insulin deficiency

diabetes mellitus.

insulin-dextrose therapy

a combination used in emergencies to lower blood potassium levels in acute hypoadrenocorticism.

insulin:glucagon ratio

ratio of insulin to glucagon; thought to determine the predominance of the action of one hormone over the other.

insulin:glucose ratio

a comparison of simultaneously obtained blood levels of immunoreactive insulin and plasma glucose. An increased ratio suggests an insulin-secreting tumor of the pancreas. A modification is the amended insulin:glucose ratio, based on the calculation:

$$\vskip13.5pt{\rm {serum\ insulin (\rmmu U/ml)\times100} \over {\rm plasma \ glucose (mg/dl) - 30}$$

immunoreactive insulin

radioimmunoassay methods are used in determining blood levels of insulin. Increased levels are found with hypoglycemia caused by functional islet cell tumors.

insulin pump

a device consisting of a syringe filled with a predetermined amount of short-acting insulin, a plastic cannula and a needle, and a pump that periodically delivers the desired amount of insulin. Sometimes used in humans, but of limited application in animals.

insulin sensitivity test, insulin response test

used to differentiate diabetes mellitus from pituitary and adrenal diabetes. A test dose of exogenous insulin will produce a rapid and marked decrease in blood glucose if the pancreas is not secreting sufficient insulin. A much less dramatic response is produced if hyperglycemia is due to excessive secretion of either pituitary or adrenocortical hormones rather than insufficient insulin production.

insulin syringe

disposable syringe with a capacity of 1 ml or less and a fine gauge needle (27-29G) attached, and graduation markings corresponding to insulin units in standard preparations. Needles may also be treated to minimize pain on injection.