198 R. G. WESTALL 
TABLE I 
THE FREE AMINO ACIDS OF HUMAN ADULT BLOOD PLASMA 
Values are expressed in mg/too ml. 


E & 4 & z 2 iS 2 S = 
z 2 as as aS fi < values 
<8 Laas} Zs us y Zz 
7, ea] < % (e) a 
a s = is é 
D iS = 
Alanine 3.4 2.9 3.90 2.5 2.85 2.4—7.6 
a-Aminobutyric acid 0.3 O0.14 0.21 0.1-0.3 
Asparagine 0.58 
Aspartic acid 0.03 0.13 0.33 0.01—-0.3 
Arginine 1.51 1.55 2.32 2.26 2.8 1.18 1.2—3.0 
Citrulline 0.5 
Cystine Tele 0.85 3.02 2.16 0.8—5.0 
Glutamic acid 0.70 0.94 0.89 0.5-1.2 
Glutamine 8.3 7-51 7.70 6.57 4.6—9.7 
Glycine 1.54 1.47 2.91 2.01 1.76 0.8—5.4 
Histidine Tes 0.90 1.42 Pasa gS yy) 1.37 0.8-3.8 
Isoleucine 0.89 0.90 1.66 2.00 20 0.75 0.7—4.2 
Leucine 1.69 1.34 2.03 2.48 1.90 1.04 I.0—5.2 
Lysine 2D. 1.97 2.97 3.68 2.40 2.09 1.4-5.8 
Methionine 0.38 0.40 0.57 0.50 0.42 0.2—1.0 
1-Methylhistidine Oni 
3-Methylhistidine 0.08 
Ornithine 0.72 Oy 0.6-0.8 
Phenylalanine 0.84 0.77 1.40 1.99 1.55 0.93 0.7—4.0 
Proline 2.36 1.95 2.61 ag 1.63 1.5—5-7 
Serine His 1.39 1.50 0.3—2.0 
Taurine 0.55 0.77 0.12 0.2—-0.8 
Threonine 1.39 1.43 2.08 2.00 ieGiit 1.61 0.9-3.6 
Tryptophane Teeyle 1.74 1.20 0.43 0.4-3.0 
Tyrosine 1.03 0.97 1.50 Wes 0.90 Tee 0.8—2.5 
Valine 2.88 2.30 2.89 3.23 2.90 2.04 1.9—4.2 

* About one quarter of this amount is cysteine®’. 
known. The cat seems to have a similar plasma amino acid pattern to the human 
except for the occurrence of a detectable amount of felinine!®. Any differences that 
exist between the amino acid patterns of males and females are smaller than those 
that occur between individuals and are probably not significant. It is, however, 
interesting to note that in pregnancy the plasma amino acid concentration in the foetus 
is higher than in the maternal blood!!, ?2. 
Uvine. Since urine is so readily accessible it is not surprising that it has been more 
extensively studied than any other body fluid. In recent years, since the first applica- 
tion of the method of paper chromatography to urine analysis by DENT, probably 
many tens of thousands of urine samples have been screened for amino acids. In many 
medical centres it has become a routine procedure and serves as a useful aid to the 
diagnosis of certain diseases. 
References p. 217/219 
