Sutton D W, Schmid-Schönbein G W
Institute for Biomedical Engineering, University of California, San Diego, La Jolla 92093-0412.
Am J Physiol. 1992 Jun;262(6 Pt 2):H1646-50. doi: 10.1152/ajpheart.1992.262.6.H1646.
Leukocytes are larger and considerably less deformable than erythrocytes, thereby causing a disproportionate effect on local blood flow, which despite their low concentration, may be significant at the organ level. To investigate the degree to which circulating leukocytes affect whole organ resistance, a hemodynamically isolated rat gracilis muscle was perfused in situ under well-controlled conditions. Comparison of organ pressure-flow data from vasodilated vasculature using normal physiological cell concentrations and perfusion pressures indicates that leukocytes (60-75% neutrophils) provide approximately 22% of the whole blood resistance despite their relatively small cell volume fraction of approximately 0.1%. On a single cell basis, each leukocyte imposes a resistance elevation equivalent to that of approximately 750 erythrocytes. Furthermore, when leukocytes are activated via pretreatment using N-formyl-methionyl-leucyl-phenylalanine or endotoxin, they show a higher resistance, accounting for 50-60% of the total resistance. These findings indicate that leukocytes play a significant role in normal skeletal muscle organ perfusion and may be a major determinant of organ perfusion during disease states.
白细胞比红细胞更大，且变形能力明显更弱，因此对局部血流产生不成比例的影响，尽管它们浓度较低，但在器官层面可能具有重要意义。为了研究循环白细胞对整个器官阻力的影响程度，在可控条件下对一只血流动力学隔离的大鼠股薄肌进行原位灌注。使用正常生理细胞浓度和灌注压力对血管舒张的脉管系统的器官压力 - 流量数据进行比较表明，白细胞（60 - 75%为中性粒细胞）尽管其细胞体积分数相对较小，约为0.1%，但却提供了约22%的全血阻力。基于单个细胞而言，每个白细胞产生的阻力升高相当于约750个红细胞产生的阻力升高。此外，当通过使用N - 甲酰 - 甲硫氨酰 - 亮氨酰 - 苯丙氨酸或内毒素进行预处理来激活白细胞时，它们表现出更高的阻力，占总阻力的50 - 60%。这些发现表明，白细胞在正常骨骼肌器官灌注中起重要作用，并且可能是疾病状态下器官灌注的主要决定因素。
