Seventeen plasma amino acids were estimated. Plasma amino acids were assorted into four groups. They are
(1) Essential amino acids (EAA): Total plasma concentrations of phenylalanine, valine, threonine, isoleucine, methionine, histidine, leucine and lysine were included as essential amino acids.
(2) Non essential amino acids (NEAA): Total amino acid concentrations of aspartate, glutamate, serine, glycine, arginine, alanine, proline, tyrosine and cystine were included as nonessential amino acids.
(3) Total amino acids (Total AA): Total plasma concentration of all amino acids
(4) Branched chain amino acids (BCAA): Total plasma amino concentrations of valine, leucine and isoleucine
Ratios between certain amino acids or groups of amino acids which are metabolically related were calculated:
(1) Fischer ratio: Fischer ratio, defined as molar ratio of branched chained amino acids (leucine, isoleucine, valine) to aromatic amino acids (Phenylalanine, tyrosine). Branched chained amino acids are mainly metabolized in muscles and aromatic amino acids are metabolized in the liver. Numerous reports have suggested that amino acid imbalance between branched chain amino acids and aromatic amino acids, leading to a decreased Fischer ratio in both experimental and clinical liver failure.
(2) Phenylalanine / Tyrosine ratio (Phe / Tyr ratio): Elevations in the plasma phenylalanine-tyrosine ratio have potential value for estimating the presence of an inflammatory disease and the catabolic state (Wannemacher RW et al, 1976).
(3) Glycine / Branched chain amino acids ratio (Gly/BCAA ratio): Changes in glycine to branched chain amino acids would indicate protein intake (Oberholzer VG and Briddon A, 1990).
(4) Glycine / Valine ratio: (Gly / Val ratio): In protein malnutrition the ratio of nonessential to essential amino acids is increased, presumably because of decreased intake of essential amino acids. A simplified and more sensitive version of this quotient is the gly / val ratio which is increased in poorly nourished individuals (Arroyave G, 1970).
Plasma free amino acid levels
The distribution pattern of these amino acids is given in table 12.1-C. When compared to healthy controls, CP patients had lower concentrations of aspartate, serine, histidine, arginine, threonine, tyrosine, valine, methionine, cystine, isoleucine, leucine and phenylalanine while plasma glutamate, glycine, proline and lysine were...