Functions of insulin in our body
Functions of insulin
Pancreas contain two types of cells:acinar cells and islets of langerhans.Acinar cells secrete digestive enzymes.Islets of langerhan secrete antidiabetic factor,a hormone called insulin.Insulin is deficient in patients with diabetes mellitus secreted by beta cells of pancreatic islets.Diabets mellitus is characterized by insulin deficiency leading to hyperglycemia,glycosuria and polyuria. Diabetes mellitus is of two forms:Type 1 and Type 2
Type 1 is insulin dependant diabetes mellitus(IDDM).Type 2 is non insulin dependant diabetes mellitus(NIDDM).Type 2 mostly occurs than Type 1. Type 1 is caused by pancreatic beta cell destruction,hence there will be complete loss of insulin.Type 2 is caused by multifactors i.e pancreatic beta cell defect,reduced tissue sensitivity or role of environment.Its insulin resistant and have low insulin production level or both.
- Insulin which is secreted by beta cells of pancreatic islets is stored and released at time of demand.The structure of Insulin is that it contains 51 amino acids arranged in two polypeptide chains(A & B).Chain A carries 21 amino acids and chain B 30 amino acids.Human insulin differs from animal insulin in amino acid number and hence in strength.Vertebrtates' insulin is very similar to human insulin and is used for clinical purposes e.g fish insulin.Half life of insulin in plasma is 5 to 6 minutes and molecular mass is about 5800 Da.
- Insulin is synthesized worldwide now.It treats diabets mellitus as diabetic patients are insulin deficient.Commonly prepared insulin cann't be given orally because of its degradation by enzymes in the stomach and gut.It can be adminstered intravenously or intramuscularly.Subcutaneous injection is the most common route of administration.Also taken by insulin pumps, insulin pens or insulin port.
- Insulin produced by human body is used to store glucose in the liver and muscles in the form of glycogen.If insulin is secreted in lower levels,it causes liver to convert glycogen into glucose that's secreted into the blood.Insulin dose is given to reduce high blood glucose level as in diabetes.
- There are several insulin formulation that include short acting,intermediate acting and long acting insulin.Theses are three main types of insulin.
- The primary effect of insulin is hypoglycemic action.And the net effect of this hormone is storage of carbohydrates,fats and proteins.
Insulin uses in treatment
As discussed above insulin is used to treat Insulin dependant diabets mellitus and non insulin dependant diabets mellitus including gestational diabetes,postpancreatectomy diabets,diabets accompanied with infection,operation,pregnancy or ketoacidosis.
Its also used in patients with intracellular potassium deficiency.
Infusion of insulin and glucose is very effective for the temporary relief of hyperkalemia in patients with renal failure.
Adverse reactions of insulin is hypoglycemia manifeted by sweating,hunger,tachycardia,tremor,palpitations.Anxiety is also observed by patient.Severe hypoglycemia leads to even convulsions and coma.Mild to moderate hypoglycemia can be treated simply by ingestion of glucose.Severe hypoglycemia canbe treated by Glucagon injection,5% glucose intravenous injection.
If too much insulin is given to the patient there will be hypoglycemia while if too little insulin is given there will be hyperglycemia.Both conditions canbe life threatening.Patients using insulin pumps who cann't control their glucose level by using conventional injections are at risk to invole in it.