Sirsjö A, Lewis D H, Nylander G
Clinical Research Center, University Hospital, Linköping, Sweden.
Int J Microcirc Clin Exp. 1990 May;9(2):163-73.
In the present study we have evaluated the activity of myeloperoxidase (MPO) in ischemic reperfused skeletal muscle of rats, as an index of polymorphonuclear leukocyte (PMNL) accumulation and its time course. A tourniquet model for temporary ischemia was used, in which one hindleg was made ischemic for 1.5, 3 or 5 hours. Muscle biopsies were taken after 12 hours reperfusion from both the injured and the uninjured legs. Controls received anesthesia only. No increase in the MPO levels was observed after 1.5 hours of ischemia followed by 12 hours of reperfusion. With the same reperfusion time and 3 or 5 hours of ischemia, there was a five-fold increase in MPO activity. Prolonging the ischemia from 3 to 5 hours did not cause any further significant MPO increase. With 3 hours of ischemia, biopsies were also taken after 0, 1, 5, 24 and 74 hours reperfusion. The results showed a time dependent increase in MPO activity. A significant increase was first seen after 5 hours reperfusion with the peak at 24 hours. After 74 hours of reperfusion the MPO activity had almost returned to control levels. The uninjured leg had MPO levels similar to those in the control. However, there was a small reduction at 5 and 12 hours of reperfusion. During the ischemic period before reperfusion, the ischemic leg showed a significant decrease in MPO activity. Severe ischemia in skeletal muscle results in a time dependent accumulation of PMNLs during reperfusion, as measured by the changes in MPO activity in the tissue.
在本研究中，我们评估了大鼠缺血再灌注骨骼肌中髓过氧化物酶（MPO）的活性，以此作为多形核白细胞（PMNL）积聚及其时间进程的指标。采用了一种用于暂时缺血的止血带模型，其中一条后腿缺血1.5、3或5小时。在再灌注12小时后，从受伤腿和未受伤腿均取肌肉活检样本。对照组仅接受麻醉。缺血1.5小时后再灌注12小时，未观察到MPO水平升高。在相同的再灌注时间下，缺血3或5小时，MPO活性增加了五倍。将缺血时间从3小时延长至5小时并未导致MPO进一步显著增加。对于缺血3小时的情况，在再灌注0、1、5、24和74小时后也取了活检样本。结果显示MPO活性呈时间依赖性增加。在再灌注5小时后首次出现显著增加，在24小时达到峰值。再灌注74小时后，MPO活性几乎恢复到对照水平。未受伤腿的MPO水平与对照组相似。然而，在再灌注5和12小时时有小幅下降。在再灌注前的缺血期，缺血腿的MPO活性显著降低。骨骼肌中的严重缺血导致再灌注期间PMNLs呈时间依赖性积聚，这可通过组织中MPO活性的变化来衡量。
