Fredholm B B, Linde B, Prewitt R L, Johnson P C
Acta Physiol Scand. 1976 Mar;97(1):48-59. doi: 10.1111/j.1748-1716.1976.tb10234.x.
The effect of sympathetic nerve stimulation (NS) and injected noradenaline (NA) or isoprenaline (Iso) on PVO2, VO2 and PtO2 was studied in isolated canine subcutaneous adipose tissue. These effects were compared to those produced by mechanical blood flow reduction (clamping). Resting VO2 measured 13.0+/- 2.3 mumol X min-1 X 100 g-1. When blood flow was reduced by 20% or less there was no significant change of VO2. Reducing blood flow to 50% of control or less by NS caused a parallel reduction in VO2, while clamping reduced VO2 significantly less. NA gave effects similar to those of NS. After NS or NA there was a period of hyperemia and increased oxygen extraction which more than compensated for the decrease in VO2 during vasoconstriction. Such a net increase in VO2 was not produced by clamping. Control PtO2 averaged 29+/-2 mmHg. NA reduced it by 70% and clamping to the same blood flow level only by 14% (p less than 0.01). Thus, a mere reduction in blood flow has little effect on PtO2, while blood flow reduction combined with redistribution of blood flow and an increased oxygen deman can lead to tissue hypoxia.
在离体犬皮下脂肪组织中，研究了交感神经刺激（NS）以及注射去甲肾上腺素（NA）或异丙肾上腺素（Iso）对静脉血氧分压（PVO2）、耗氧量（VO2）和组织氧分压（PtO2）的影响。将这些影响与机械性血流减少（钳夹）所产生的影响进行了比较。静息状态下的VO2为13.0±2.3 μmol·min-1·100 g-1。当血流减少20%或更少时，VO2无显著变化。通过NS将血流减少至对照值的50%或更低时，VO2会随之平行降低，而钳夹导致VO2降低的幅度明显较小。NA产生的作用与NS相似。在NS或NA作用后，会出现一段时间的充血和氧摄取增加，这足以弥补血管收缩期间VO2的降低。钳夹不会产生这种VO2的净增加。对照PtO2平均为29±2 mmHg。NA使其降低了70%，而将血流钳夹至相同水平时仅降低了14%（p<0.01）。因此，单纯的血流减少对PtO2影响很小，而血流减少与血流重新分布以及氧需求增加相结合会导致组织缺氧。
