Effect of increased Hb-O2 affinity on VO2max at constant O2 delivery in dog muscle in situ.
Effect of increased Hb-O2 affinity on VO2max at constant O2 delivery in dog muscle in situ.
复制标题
狗肌肉原位恒定 O2 输送时 Hb-O2 亲和力增加对 VO2max 的影响。
DOI：
10.1152/jappl.1991.70.6.2656
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发表时间：
1991
期刊：
影响因子：
--
通讯作者：
Wagner,PD
中科院分区：
文献类型：
--
作者：
Hogan,MC;Bebout,DE;Wagner,PD
我们研究了增加血红蛋白- (Hb) O2亲和力对肌肉最大氧摄取（VO2max）的影响，而肌肉血流量、[Hb]、HbO2饱和度以及向工作肌肉的氧输送（肌肉血流量X动脉氧含量）与对照组保持不变。在离体犬腓肠肌处于最大工作状态（等距强直收缩）时测量VO2max。用正常血液[血红蛋白O2半饱和压(P50) = 32.1 +/- 0.5 (SE) Torr]或喂食了氰酸钠（150 mg.kg-1）的狗的血液交替泵灌注肌肉。第1天)持续3-4周（P50 = 23.2 +/- 0.9）。在这两种情况下（n = 8），动脉血PO2被设定在200 Torr左右，以使动脉血完全饱和，从而产生相同的动脉血氧含量，肌肉血流量被设定为106 ml.100 g-1。min-1，所以两种情况下的氧气输送是一样的。正常血（对照）灌注时VO2max为11.8 +/- 1.0 ml.min-1.100 g-1，低p50血灌注时VO2max为9.8 +/- 0.7 ml.min-1.100 g-1，降低17% （P < 0.01）。在低p50条件下，平均肌肉流出静脉PO2也显着降低（26 +/- 3 vs. 30 +/- 2 Torr; P < 0.01），对于O2扩散的毛细血管驱动压力的估计，平均毛细血管PO2 （45 +/- 3 vs. 51 +/- 2 Torr）。然而，在不同的条件下，估计的肌肉O2扩散能力没有差异。（摘要删节250字）
We investigated the effect of increasing hemoglobin- (Hb) O2 affinity on muscle maximal O2 uptake (VO2max) while muscle blood flow, [Hb], HbO2 saturation, and thus O2 delivery (muscle blood flow X arterial O2 content) to the working muscle were kept unchanged from control. VO2max was measured in isolated in situ canine gastrocnemius working maximally (isometric tetanic contractions). The muscles were pump perfused, in alternating order, with either normal blood [O2 half-saturation pressure of hemoglobin (P50) = 32.1 +/- 0.5 (SE) Torr] or blood from dogs that had been fed sodium cyanate (150 mg.kg-1.day-1) for 3-4 wk (P50 = 23.2 +/- 0.9). In both conditions (n = 8) arterial PO2 was set at approximately 200 Torr to fully saturate arterial blood, which thereby produced the same arterial O2 contents, and muscle blood flow was set at 106 ml.100 g-1.min-1, so that O2 delivery in both conditions was the same. VO2max was 11.8 +/- 1.0 ml.min-1.100 g-1 when perfused with the normal blood (control) and was reduced by 17% to 9.8 +/- 0.7 ml.min-1.100 g-1 when perfused with the low-P50 blood (P less than 0.01). Mean muscle effluent venous PO2 was also significantly less (26 +/- 3 vs. 30 +/- 2 Torr; P less than 0.01) in the low-P50 condition, as was an estimate of the capillary driving pressure for O2 diffusion, the mean capillary PO2 (45 +/- 3 vs. 51 +/- 2 Torr). However, the estimated muscle O2 diffusing capacity was not different between conditions.(ABSTRACT TRUNCATED AT 250 WORDS)