Table 2. Leucine kinetics comparing the study groups during the four leucine flux measurementsa

GroupQKIC (μmol/kg/h)CKIC (μmol/kg/h)SKIC (μmol/kg/h)DKIC (μmol/kg/h)BalanceKIC (μmol/kg/h)VCO2 (ml/min)Plasma Leucine (μmol/L)
a B-HD, HD, and N represent, respectively, predialysis, hemodialysis patients, and normal subjects. Q, D, C, and S, represent, respectively, leucine flux, protein degradation, leucine oxidation, and protein synthesis. Balance represents net flux of leucine into protein. KIC indicates that calculations were derived from plasma 13C KIC enrichment. During Flux 1, 2, and 3, D = Q. During Flux 4, D = Q − 67 μmol/kg/h. VCO2 is CO2 production rate. All P values listed were derived from one-way ANOVA comparing the three study groups within each flux period.
b P < 0.05 B-HD versus N.
c P < 0.05 HD versus N.
d P < 0.05 B-HD versus HD.
Flux 1
    B-HD114 ± 718 ± 2.396 ± 6114 ± 7−18 ± 2.3256 ± 26137 ± 8.6b
    HD126 ± 417 ± 2.1107 ± 4126 ± 4−17 ± 2.1274 ± 41143 ± 13.4c
    N116 ± 621 ± 2.694 ± 4116 ± 6−21 ± 2.6225 ± 19181 ± 14.6
    P0.320.440.140.320.440.570.042
Flux 2
    B-HD89 ± 312 ± 1.4b77 ± 3.789 ± 3−12 ± 1.4b270 ± 2186 ± 4.8
    HD98 ± 611 ± 1.6c87 ± 5.398 ± 6−11 ± 1.6c295 ± 4090 ± 9.2
    N94 ± 518 ± 1.176 ± 4.794 ± 5−18 ± 1.1250 ± 1698 ± 10.8
    P0.390.0210.220.390.0210.590.59
Flux 3
    B-HD77 ± 39 ± 1.1b68 ± 3.877 ± 3−9 ± 1.1b290 ± 2369 ± 5.7
    HD82 ± 78 ± 1.0c74 ± 6.182 ± 7−8 ± 1.0c319 ± 5173 ± 7.1
    N84 ± 514 ± 1.170 ± 5.184 ± 5−14 ± 1.1273 ± 2075 ± 9.1
    P0.630.0050.670.630.0050.650.79
Flux 4
    B-HD139 ± 335 ± 3.8105 ± 5.2d73 ± 332 ± 4302 ± 28238 ± 21
    HD174 ± 1829 ± 4.6145 ± 15.4c107 ± 1838 ± 5324 ± 47228 ± 13
    N152 ± 739 ± 2.8113 ± 5.985 ± 728 ± 3289 ± 27246 ± 16
    P0.090.240.020.090.240.780.80