TY - JOUR
T1 - Free amino acids in plasma, red blood cells, polymorphonuclear leukocytes, and muscle in normal and uraemic children
AU - Canepa, Alberto
AU - Divino Filho, José Carolino
AU - Gutierrez, Alberto
AU - Carrea, Alba
AU - Forsberg, Ann Marie
AU - Nilsson, Eva
AU - Verrina, Enrico
AU - Perfumo, Francesco
AU - Bergström, Jonas
PY - 2002
Y1 - 2002
N2 - Background. The aims of this study were to investigate free amino acid (AA) concentrations in plasma, red blood cells (RBC), polymorphonuclear granulocytes (PMN), and muscle, sampled at the same time, in normal and uraemic children. Methods. Twelve apparently well-nourished chronically uraemic children (five females) aged a mean of 9.4±4.8 (range 1.7-17.7) years and 13 age-matched normal children were studied. Venous blood and muscle samples for AA analyses were taken simultaneously after an overnight fast. Results. The intracellular AA patterns in the three cellular compartments were qualitatively similar, but the absolute intracellular concentrations were higher in muscle than in PMN, which had higher values than in RBC. The AA patterns in plasma, RBC, PMN, and muscle in the uraemic children have many similarities; typical features being low branched-chain AA (BCAA), tyrosine, and serine concentrations and variably high concentrations of some non-essential AA. Among the individual AA, there were only few correlations between their concentrations in the three cell compartments. Conclusions. The lack of correlation between the concentrations in RBC, PMN, and muscle for most of the AA indicates that there is no close association in the same subject between individual free AA concentrations in various types of cells, presumably because of differences in metabolism and function. Consequently, one should be cautious in assuming that AA concentrations, determined in RBC or PMN, reflect the concentrations in muscle cells. Therefore, these preliminary observations do not support the hypothesis that RBC and PMN AA analysis can be considered as a suitable alternative to muscle AA determination.
AB - Background. The aims of this study were to investigate free amino acid (AA) concentrations in plasma, red blood cells (RBC), polymorphonuclear granulocytes (PMN), and muscle, sampled at the same time, in normal and uraemic children. Methods. Twelve apparently well-nourished chronically uraemic children (five females) aged a mean of 9.4±4.8 (range 1.7-17.7) years and 13 age-matched normal children were studied. Venous blood and muscle samples for AA analyses were taken simultaneously after an overnight fast. Results. The intracellular AA patterns in the three cellular compartments were qualitatively similar, but the absolute intracellular concentrations were higher in muscle than in PMN, which had higher values than in RBC. The AA patterns in plasma, RBC, PMN, and muscle in the uraemic children have many similarities; typical features being low branched-chain AA (BCAA), tyrosine, and serine concentrations and variably high concentrations of some non-essential AA. Among the individual AA, there were only few correlations between their concentrations in the three cell compartments. Conclusions. The lack of correlation between the concentrations in RBC, PMN, and muscle for most of the AA indicates that there is no close association in the same subject between individual free AA concentrations in various types of cells, presumably because of differences in metabolism and function. Consequently, one should be cautious in assuming that AA concentrations, determined in RBC or PMN, reflect the concentrations in muscle cells. Therefore, these preliminary observations do not support the hypothesis that RBC and PMN AA analysis can be considered as a suitable alternative to muscle AA determination.
KW - Amino acids
KW - Leukocytes
KW - Muscle
KW - Plasma
KW - Red blood cells
KW - Uraemic children
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M3 - Article
C2 - 11865086
AN - SCOPUS:0036194620
VL - 17
SP - 413
EP - 421
JO - Nephrology Dialysis Transplantation
JF - Nephrology Dialysis Transplantation
SN - 0931-0509
IS - 3
ER -