Cooper D M, Wasserman D H, Vranic M, Wasserman K
Am J Physiol. 1986 Aug;251(2 Pt 1):E209-14. doi: 10.1152/ajpendo.1986.251.2.E209.
The purpose of this study was to assess whether breathing high or low concentrations of O2 could affect glucose turnover during exercise in man. Ten healthy subjects performed two constant work-rate exercise tests, one when the fraction of inspired O2 (FIO2) was 0.15 and the other at the same work rate but when the FIO2 was 0.80. The work rate for each subject was chosen so that blood lactate would be elevated during hypoxia, but would be lower during hyperoxia. Glucose appearance (Ra) and disappearance (Rd) were measured using the primed, constant infusion of [3-3H]glucose. Although the work rate was the same during hypoxia and hyperoxia in each subject, hypoxic exercise was accompanied by a significantly larger rest to exercise increase in Rd (delta Rd) compared with hyperoxia by 265%. Similarly, delta Ra was greater during hypoxia than during hyperoxia by 188%. Lactate to pyruvate ratios were significantly higher during hypoxic exercise suggesting a shift in the cell redox to a more reduced state. Insulin and glucagon were not affected by the FIO2, but both epinephrine and norepinephrine were increased during hypoxic exercise, which may explain the increase in Ra. The regulation of blood glucose during exercise in vivo appears to be dependent on the availability of oxygen to the working muscle cells.
本研究的目的是评估在人体运动期间呼吸高浓度或低浓度氧气是否会影响葡萄糖代谢。10名健康受试者进行了两项恒定工作率运动测试，一项测试中吸入氧气分数（FIO2）为0.15，另一项测试在相同工作率下但FIO2为0.80。为每个受试者选择的工作率使得在低氧期间血乳酸会升高，但在高氧期间会降低。使用[3-3H]葡萄糖的预充式恒定输注法测量葡萄糖的出现率（Ra）和消失率（Rd）。尽管每个受试者在低氧和高氧期间的工作率相同，但与高氧相比，低氧运动时Rd从休息到运动的增加量（ΔRd）显著更大，高出265%。同样，低氧期间的ΔRa比高氧期间大188%。低氧运动期间乳酸与丙酮酸的比率显著更高，表明细胞氧化还原状态向更还原的状态转变。胰岛素和胰高血糖素不受FIO2影响，但低氧运动期间肾上腺素和去甲肾上腺素均增加，这可能解释了Ra的增加。体内运动期间血糖的调节似乎取决于工作肌肉细胞的氧气供应情况。
