





FREE AMINO ACIDS OF BLOOD AND URINE 245 
DAB EIR 
ERYTHROCYTES FREE AMINO ACID CONTENT AT DIFFERENT STAGES 
OF THE SEPARATION PROCESS 
Normal adult woman. Values are expressed in ssmoles/100 g water. 
Erythrocytes Non- 
—_———— washed 
Amuno acid Plasma Non After After rst After 2nd erythrocytes| 
: PVP NaCl NaCl plasma 
Piashed treatment washing washing ratio 
Phosphoserine 0.44 7.85 6.16 = 37-9 17.84 
Taurine 3-71 3.85 3:2 — 4.62 1.04 
Methionine sulfoxides 0.55 1.54 — — 0.92 2.80 
Aspartic acid O.11 21.25 19.40 19.60 18.63 193.18 
Threonine 9.05 9.55 2.16 2.20 2707, 1.06 
Serine 8.50 7.24 6.00 6.10 6.01 0.85 
Glutamine 12.50 40.80 32.80 35-70 34.19 3-75 
Proline 23.00 P2477, 2.00 1.50 1.10 0.54 
Glutamic acid 2.00 23.10 26.80 24.20 23.41 11.55 
Citrulline 1.85 0.31 0.15 _- 0.17 
Glycine 18.20 31.88 28.30 28.20 28.34 E75 es 
Alanine 26.30 27.10 26.30 19.70 15.40 1.03 
a-Aminobutyric acid 1.40 007) — — — 0.88 
Valine 18.50 14.17 2.60 2.50 0.92 0.77 
Cystine 1/, 2.40 Traces — — — — 
Methionine 2.00 1.85 Traces 0.50 0.40 0.93 
Isoleucine 6.80 6.01 1.10 0.90 0.40 0.88 
Leucine II.40 10.01 2.16 1.70 0.49 0.88 
Tyrosine 5.90 7.39 2.00 1.69 1.54 1.25 
Phenylalanine 5.90 5.24 1.39 1.08 0.62 0.89 
p-alanine oO 0.77 — — — — 
p-aminoisobutyric acid Traces Traces = = = = 
Ornithine 6.04 13:2 4.79 — 2.63 2.20 
Lysine 13.25 12.92 4.99 — 3.60 0.92 
1-Methylhistidine fo) 1.28 0.98 — Traces — 
Histidine 7.05 7-53 2.79 — 1.66 1.07 
3-Methylhistidine Traces Traces — = = = 
Arginine 5-32 2.00 oO — oO 0.39 
Urea 550 517 52-7 3 30 4 
Ammonia 50.89 88.81 76.85 — 76.58 1.56 

are much higher than in the surrounding plasma, and they agree reasonably with 
those published by ScHRAM AND Husrinont?® and by McMenamy et al.*! although 
in the latter study, the methods used for amino acid determination and preparation 
of the samples were quite different from those used in the present study. Although 
we have no evidence that free amino acids could have leaked away from leucocytes 
and platelets during the cell separation process we have used, this possibility must 
be kept in mind since, as will be seen, it actually happens to a large extent with 
erythrocytes when plasma is washed off. 
c) Erythrocytes. To obtain separation of the leucocytes and platelets from the eryth- 
rocytes, use was made of spontaneous sedimentation of the red blood cells in 
an isotonic (pH 7.3) buffered solution containing 2°, polyvinylpyrollidone. This 
process was repeated twice, the erythrocytes were packed by centrifugation and the 
References p. 261/262 
