The abnormal amino acid profile and altered distribution of some amino acids between the extra- and intracellular compartments is currently recognized as a part of metabolism abnormalities in hemodialyzed uremic patients associated with prognosis. The aim of this study was to investigate the pattern of HD influence on the extra- and intracellular amino acid concentrations in neutrophil homogenates and in blood serum. Before HD, the concentrations of arginine (64 vs 33 micromol/l) and cysteine (70 vs 40 micromol/l) were significantly higher in the uremic blood serum, but the concentrations of five amino acids, i.e. serine, threonine, alanine, proline, and valine, were significantly decreased in the uremic serum. The concentrations of arginine (7.95 vs 5.2 micromol/l), tyrosine (14.3 vs 12.5 micromol/l) and phenylalanine (10.7 vs 9.5 micromol/l) were significantly elevated in neutrophil homogenate from uremic patients before HD and after HD for arginine (8.73 micromol/l). We found a substantial increase of blood serum arginine concentration at all evaluated time points of HD from 64 to 191 micromol/l. The concentration of 8 amino acids were found to be significantly decreased in blood serum during HD. We may assume amino acid concentration changes in chronic uremia partly attributed to malnutrition, may be actually associated with inflammatory pathomechanisms, the hypothesis worth verifying in further studies.