化学性急性肺损伤时肺内皮细胞及血液流变学的实验研究

目的探讨化学性急性肺损伤(ALI)时肺循环血液流变学、肺毛细血管内皮损伤的基本变化及其临床意义.方法采用肺动脉插管技术、循环内皮细胞(CEC)分离技术及血液流变学检测方法,直接监测ALI时肺循环血液、外周血液的血液流变学指标及CEC变化情况.结果CEC在急性肺损伤早期即明显增加,在肺循环中更为明显[从(2.06±0.48)个/0.9μl上升到(5.31±0.63)个/0.9μl];高切变率(200 s-1、30 s-1)下,各组大鼠全血黏度未见明显变化;低切变率(5 s-1、1 s-1)下肺循环血液全血黏度、红细胞压积明显增加,与对照组比较,差异有显著性(P＜0.05),红细胞数量也呈增加趋势,血中血小板数量亦有减少.结论肺循环状况恶化是ALI发病的关键环节;肺毛细血管内皮细胞(PCEC)的损伤和功能障碍可能是ALI时一系列病理过程的共同的启动点;GEC的检测为ALI的诊断提供了一个新的敏感客观的反映指标.

Study on the changes in circulating endothelial cells and hemorheology of lung in rats with acute lung injury by chemicals

OBJECTIVE: To investigate the mechanism of pulmonary circulation obstacle in chemicals-induced acute lung injury and its clinical significance. METHOD: Pulmonary arterial intubation, circulating endothelial cells (CEC) isolation and hemorheology detection technique were used to observe the changes of CEC numbers and hemorheology in rat pulmonary vascular system during oleic acid-induced acute lung injury (ALI). RESULTS: The numbers of CEC were obviously increased even in the early phase of ALI [from (2.06 +/- 0.48)/0.9 micro l to (5.50 +/- 0.54)/0.9 micro l]; there was no obvious change in whole blood viscosity under high shear rate (200 s(-1), 30 s(-1)) but the whole blood viscosity and hematocrit were remarkably increased in pulmonary artery blood at low shear rate (5 s(-1), 1 s(-1)) (P < 0.05). Erythrocytes had increasing tendency, whereas platelets were also decreased but there was no statistical significance. CONCLUSION: The deterioration of pulmonary circulation may be the key point in the pathogenesis of ALI; the injury and dysfunction of pulmonary capillary endothelial cells (PCEC) may be the common starting phase in the pathological processes of ALI; the detection of CEC may offer a new valuable and sensitive index for diagnosis of ALI.