Zawieja D C, Greiner S T, Davis K L, Hinds W M, Granger H J
Microcirculation Research Institute, College of Medicine, Texas A&M University, College Station 77843-1114.
Am J Physiol. 1991 Jun;260(6 Pt 2):H1935-43. doi: 10.1152/ajpheart.1991.260.6.H1935.
The effects of oxygen-derived free radicals on the contractile activity of the mesenteric collecting lymphatics were evaluated in the anesthetized rat. Lymphatic contractions were monitored before, during and after the application of oxyradicals. Contraction frequency (F), stroke volume (SV), ejection fraction (EF), contraction propagation (PC), and lymph pump flow (LPF) were determined from the lymphatic diameter tracings. Oxyradicals were generated using hypoxanthine and xanthine oxidase. Exposure to oxyradicals inhibited the lymphatic pumping mechanism: 1) F fell from 15.5 +/- 0.8 to 0.8 +/- 0.7 beats/min; 2) EF went from 0.44 +/- 0.02 to 0.08 +/- 0.04; 3) PC dropped from 92 +/- 2 to 56 +/- 8%; and 4) LPF fell precipitously from 41.0 +/- 5.2 to 0.7 +/- 0.4 nl/min. The effects of the oxyradicals were attenuated by superoxide dismutase, implicating superoxide anion as one of the predominant causative agents. We conclude that oxyradicals significantly inhibit the lymph pump and that this inhibition could be a factor contributing to the formation of interstitial edema during inflammation.
在麻醉大鼠中评估了氧衍生自由基对肠系膜集合淋巴管收缩活性的影响。在施加氧自由基之前、期间和之后监测淋巴管收缩情况。从淋巴管直径描记图中确定收缩频率（F）、每搏输出量（SV）、射血分数（EF）、收缩传播（PC）和淋巴泵流量（LPF）。使用次黄嘌呤和黄嘌呤氧化酶产生氧自由基。暴露于氧自由基会抑制淋巴泵机制：1）F从15.5±0.8降至0.8±0.7次/分钟；2）EF从0.44±0.02降至0.08±0.04；3）PC从92±2降至56±8%；4）LPF从41.0±5.2急剧降至0.7±0.4 nl/分钟。超氧化物歧化酶可减弱氧自由基的作用，提示超氧阴离子是主要致病因子之一。我们得出结论，氧自由基显著抑制淋巴泵，这种抑制可能是炎症期间导致间质水肿形成的一个因素。
