Table 3.

Plasma concentrations (micromoles per liter) and urinary excretion (micromoles per mole creatinine) of amino acids and amines in nondialyzed CKD patients

VariablesPlasma ConcentrationUrinary Excretion
CKD2–3CKD4–5P ValueCKD2–3CKD4–5P Value
Total AA2512.4±411.02597.7±470.20.49246.5±107.1324.8±303.20.90
Total essential AA1006.0±234.1975.9±244.50.6871.8±35.4104.7±101.40.80
Total nonessential AA1506.4±249.41621.8±284.40.13200.1±126.8220.1±204.50.56
Total branched chain AA421.4±133.5391.6±142.90.416.1±7.27.1±15.80.18
Alanine305.3±100.0334.3±105.00.3223.8±21.530.7±29.20.54
Arginine88.5±25.793.1±33.30.587.8±6.68.2±6.00.42
Asparagine38.6±10.443.0±9.20.117.2±3.314.7±14.70.07
Aspartate6.1±23.45.6±15.90.5612.7±15.09.0±22.40.08
Citrulline35.9±16.361.8±23.6<0.001a1.0±1.27.1±14.3<0.001a
Glutamine514.8±68.3536.6±71.60.2725.0±15.831.4±44.20.40
Glutamate72.1±45.396.0±105.40.8329.8±61.519.3±25.10.50
Glycine185.3±48.1189.5±73.10.7169.9±44.867.6±69.60.32
Histidine74.9±11.277.7±17.50.6134.9±23.430.0±26.00.30
Isoleucine76.7±26.975.2±30.40.800.9±1.90.6±2.90.11
Leucine124.8±45.1104.9±53.00.122.2±3.52.2±5.90.23
Lysine186.3±45.7192.4±45.20.5310.4±10.326.5±30.70.11
Methionine36.6±11.838.3±11.20.591.2±1.11.3±1.90.50
Ornithine53.9±22.666.9±21.80.01a15.4±57.11.8±5.10.33
Phenylalanine62.9±12.070.5±17.90.154.9±2.96.7±7.10.94
Proline212.4±71.8243.0±67.50.122.6±2.613.8±18.5<0.001a
Serine83.4±20.780.7±18.10.6221.3±10.225.4±19.70.73
Threonine101.6±31.999.8±28.60.9211.1±10.520.9±29.10.43
Tryptophan55.5±12.342.3±13.4<0.001a4.5±2.54.8±3.90.88
Tyrosine66.9±22.863.3±22.90.596.5±3.97.5±6.90.94
Valine219.9±64.6211.6±73.60.693.0±2.64.3±7.90.54
ADMA0.57±0.291.02±0.48<0.001a2.37±0.931.51±1.43<0.001a
SDMA1.54±3.480.85±0.580.692.85±0.932.89±2.910.06
Hydroxykynurenine1.19±0.392.82±1.22<0.001a0.13±0.100.45±0.900.15
  • All values are mean ± SD. CKD2–3, CKD stages 2 and 3; CKD4–5, CKD stages 4 and 5; AA, amino acid; ADMA, asymmetric dimethylarginine; SDMA, symmetric dimethylarginine.

  • a P<0.05.