Table 2.

Amino acid concentrations in the rat cortex and hippocampus following a five week oral administration of water or prebiotic.

[Amino acid] (pmol/mg tissue)
Amino acid	Water	FOS	GOS
Frontal cortex
l-Alanine	90.5 ± 7.9	100.9 ± 8.4	108.6 ± 6.6
d-Alanine	2.6 ± 0.4	2.4 ± 0.2	2.3 ± 0.3
l/d-Alanine	37.7 ± 5.9	42.8 ± 3.2	42.2 ± 2.0
Glutamate	783.9 ± 75.6	837.3 ± 48.0	822.3 ± 47.9
Glutamine	618.9 ± 52.7	645.4 ± 44.7	700.5 ± 44.0
Glut/Gln	1.27 ± 0.06	1.32 ± 0.1	1.18 ± 0.03
l-Serine	141.4 ± 13.6	152.8 ± 6.0	161.8 ± 10.9
d-Serine	40.3 ± 2.9	48.7 ± 1.7	53.6 ± 3.4⁎
l/d-Serine	3.5 ± 0.23	3.1 ± 0.07	3.0 ± 0.14
Hippocampus
l-Alanine	99.7 ± 9.5	92.0 ± 6.2	97.5 ± 9.3
d-Alanine	2.8 ± 0.4	2.6 ± 0.2	2.3 ± 0.2
l/d-Alanine	36.9 ± 3.9	36.5 ± 3.7	42.0 ± 2.5
Glutamate	705 ± 79.8	649 ± 59.3	643.9 ± 68.1
Glutamine	545.1 ± 58.2	480.1 ± 52.6	504.6 ± 48.0
Glut/Gln	1.30 ± 0.04	1.38 ± 0.09	1.27 ± 0.05
l-Serine	121.4 ± 12.4	111.4 ± 7.8	111.9 ± 9.3
d-Serine	37.4 ± 4.1	34.6 ± 2.1	35.3 ± 3.4
l/d-Serine	3.3 ± 0.03	3.2 ± 0.04	3.2 ± 0.08

^⁎p < 0.05 compared to water.