Table 1.
Amino acid concentrations and enrichments in blood and muscle fluid in the Basal period (Basal) and during amino acid infusion (AA)
| Basal | AA | |
|---|---|---|
| Blood | ||
| Leucine, μmol/L | 114 ± 7 | 280 ± 14# |
| Phenylalanine, μmol/L | 57 ± 5 | 204 ± 19# |
| d9-leucine, MPE | 4.5 ± 0.1 | 4.4 ± 0.1 |
| 13C6-phenylalanine, MPE | 5.8 ± 0.3 | 8.5 ± 0.8 |
| Muscle fluid | ||
| Leucine, μmol/L | 140 ± 19 | 223 ± 39* |
| Phenylalanine, μmol/L | 106 ± 11 | 214 ± 39* |
| d9-leucine, MPE | 3.1 ± 0.1 | 4.2 ± 0.2# |
| 13C6-phenylalanine, MPE | 2.4 ± 0.2 | 7.2 ± 0.8# |
| Blood MPE/muscle fluid MPE | ||
| d9-leucine | 1.5 ± 0.1 | 1.1 ± 0.1# |
| 13C6-phenyalanine | 2.5 ± 0.1† | 1.2 ± 0.1#† |
Values are means ± SE; MPE, molar percent excess.
Basal versus AA infusion:
#
P < 0.01
*
P ≤ 0.05.
D9-leucine versus 13C6-phenylalanine:
†
P < 0.01.