Table 5.

Effects of hypoxia and bed rest on selected amino acid concentrations in plasma and red blood cells.

	Ambulatory		Bed rest		P
	Normoxia	Hypoxia	Normoxia	Normoxia	Bed rest effect	Hypoxia effect	Interaction
Plasma amino acid concentrations
Homocysteine (μmol × L-1)	15.3 ± 1.7	17.0 ± 1.4	14.7 ± 1.4	16.2 ± 1.4	0.38	0.003	0.93
Cysteine (μmol × L-1)	294 ± 12	299 ± 11	277 ± 10	304 ± 11	0.45	0.005	0.27
Glycine (μmol × L-1)	172 ± 9	185 ± 10*	196 ± 12	185 ± 12	0.04	0.78	0.01
Glutamate (μmol × L-1)	61 ± 4	69 ± 5	62 ± 3	67 ± 3	0.81	0.03	0.59
Glutamine (μmol × L-1)	541 ± 10	515 ± 9	552 ± 21	522 ± 7	0.55	0.01	0.86
Pyroglutamic acida (μmol × L-1)	1.02 ± 0.08	0.90 ± 0.06	1.01 ± 0.07	0.89 ± 0.06	0.85	0.04	0.86
Erythrocyte amino acid concentrations
Cysteine (μmol × L-1)	70 ± 3	79 ± 3	72 ± 4	70 ± 3	0.20	0.33	0.07
Glycine (μmol × L-1)	368 ± 11	389 ± 13	372 ± 12	393 ± 12	0.49	<0.001	0.98
Glutamate (μmol × L-1)	477 ± 24	481 ± 18	448 ± 16	478 ± 17	0.33	0.16	0.37
Glutamine (μmol × L-1)	1053 ± 147	1015 ± 209	1042 ± 141	1000 ± 215	0.79	0.73	0.97

Data are expressed as mean ± SEM. Data were analyzed with the use of a 2-factor repeated measure ANOVA or ANCOVA. Post hoc analysis was performed using Student t-test with Bonferroni correction. ^∗p < 0.05 hypoxia versus normoxia.