Akademik

Arginine
An amino acid, one of the 20 amino acids that serve as the building blocks in protein. Arginine is not an "essential" amino acid. (It is not essential to the diet, but can be made by the body from other substances.) However, it is usually considered essential to the diet for children so they can grow normally. Lack of arginine in the diet impairs growth and in adult males it decreases the sperm count. Arginine is available in foods such as turkey, chicken and other meats and as L-arginine in supplements. Babies born without an enzyme called phosphate synthetase have arginine deficiency syndrome. Adding arginine to their diet permits normal growth and development. Arginine is the direct metabolic precursor (forerunner) of urea, the dominant nitrogenous waste product. Arginine was discovered in protein in 1895. It is abbreviated Arg.
* * *
2-Amino-5-guanidinopentanoic acid; one of the amino acid s occurring among the hydrolysis products of proteins, particularly abundant in the basic proteins such as histones and protamines. A dibasic amino acid.
- a. deiminase an enzyme catalyzing the hydrolytic deamination of l-a. to l-citrulline and ammonia. Cf.:nitric oxide synthase.
- a. glutamate a compound composed of a. and glutamic acid, given intravenously to detoxify ammonia; used in the treatment of ammoniemia resulting from liver dysfunction.
- a. hydrochloride a form of a. used for intravenous administration as an adjunct in the treatment of encephalopathies associated with liver diseases and ammoniacal azotemia.
- a. phosphate SYN: phosphoarginine.

* * *

ar·gi·nine 'är-jə-.nēn n a crystalline basic amino acid C6H14N4O2 derived from guanidine abbr. Arg

* * *

n.
an amino acid that plays an important role in the formation of urea by the liver.

* * *

ar·gi·nine (ahrґjĭ-nēn) 1. a nonessential amino acid, 2-amino-5-guanidinovaleric acid, produced by the hydrolysis or digestion of proteins. It is one of the hexone bases and supplies the amidine group for the synthesis of creatine. Arginine is also formed by the transfer of a nitrogen atom from aspartate to citrulline in the urea cycle. It then gives off urea, to form ornithine. Symbols Arg and R. See table at amino acid. 2. [USP] a preparation of L-arginine used in the treatment of hyperammonemia and as a diagnostic aid in the assessment of pituitary function (see arginine stimulation test, under test).

Medical dictionary. 2011.