488 E. MUSSINI AND F. MARCUCCI 
tative with an average error of approx. 3°%. The reproducibility was satisfactory 
in duplicate experiments. Table II shows that, after separation, the sum of the amino 
acids gave an average of 87°% present in the extract added to the column. The 
spectrum of the amino acids present in rat brain is reported in Fig. 1 and includes 
cysteic acid, glycerophosphoethanolamine, taurine, aspartic acid, threonine, serine, 
TABLE II 
RECOVERY OF FREE AMINO ACIDS PRESENT IN POOLED RAT BRAINS 


a Present before Found after ; 
ne le chromatography chromatography se ay 
me (mg|r00 g) (mg|r00 g) (7) 
I 3.10 2.70 87.0 
2 3.00 2.63 87.6 
3 3.00 2.80 93-3 
4 3.00 2.44 Sieg 
5 3.10 2.88 92.9 
6 3.00 2.41 80.3 
Average 3.03 2.64 87.1 

asparagine, glutamine, glutamic acid, alanine and y-aminobutyric acid (GABA). 
Table III shows that the composition of the amino acids in rat brain changes 
according to the age of the rats. Therefore, when treatment was carried out, it was 
found necessary to use rats of the same age. The amino acids shown in Table IV 
will not be reported because they are present in concentrations lower than 6.0 mg/ 
PAB EAI 
FREE AMINO ACIDS OF RAT BRAIN ACCORDING TO THE AGE OF THE RATS 
Values are expressed in mg/too g. 



T258 200 g 350 & 
Amino acid 
wei Brtract Hvarolyeed — atygey Hoar Obed Brtyggg “Hy drolyxed 
Cysteic acid Trace 15.8 dirace 15.0 Trace 15.0 
Taurine 29.8 32.2 52.9 37-2 39.2 25.7 
Aspartic acid 28.9 68.4 40.1 67.7 38.0 63.0 
Threonine 6.1 4.7 8.6 Trace 9.0 4.4 
Serine 9.5 10.0 8.5 5.8 13.0 8.8 
Asparagine, Glutamine 20.3 -— 49.8 — 40.0 — 
Glutamic acid 76.3 110.7 70.2 149.4 107.7 17 Aleo 
Alanine ih TES} 16.3 8.0 30.7 16.3 34.0 
GABA 26.0 32.0 33-6 33-2 30.0 28.3 

100 g of fresh tissue. At this concentration the method reaches the limit of sensitivity. 
Glutamic acid, alanine and aspartic acid were also present in a conjugated form. 
The effect of a number of drugs on the free amino acids was evaluated. It was 
decided to use monoamineoxidase (MAO) inhibitors and reserpine for the following 
reasons: 
References p. 492 
