CATECHOLAMINE ASSAY BY RADIOENZYMATIC METHOD - A PROTOCOL

Abstract

Catecholamines are a group o f compounds identified by the catechol nucleus. The significant catecholaminesfound naturally in the body are epinephrine, nor- epinephrine and dopamine. They are found in varioustissues o f the body like brain, adrenals, GIT, blood, urine and cerebrospinal fluid in picogram quantities.Knowledge of catecholamines is important in the diagnosis and management o f pheochromocytoma, CNStumours like neuroblastoma, Diabetes mellitus, hypertension, coronary disease, angina pectoris, myocardialinfarction etc. Analytical techniques for determination o f catecholamines have been developed which aregenerally based upon the use o f isolated enzyme catechol-O-methyltransferase (COMT) to transfer aradioactive methyl group from S-adenosyl-L-methionine (SAM) to an endogenous catecholamine acceptormolecule to form a radioactive O-methyl catecholamine derivative. This article gives a basic out line ofthe catecholamine assay along with a simplified protocol that can be easily performed in the laboratory.

Keywords

• catecholamine
• radioenzy matic assay
• catechol-o -methyltransferase (c o m t )