VILI大鼠血清对内皮细胞通透性的影响及其作用机制的研究

目的 研究大潮气量机械通气后大鼠血清炎性介质对内皮细胞骨架及单层细胞通透性的影响及乌司他丁的治疗作用,探讨机械通气生物伤引起肺水肿的细胞和分子机制.方法 将30只SD大鼠分成3组:正常潮气量机械通气组;大潮气量机械通气组;大潮气量机械通气 乌司他丁组.收集机械通气后的3组大鼠的血清,并将这3组血清分别作用于ECV-304细胞,观察聚合型肌动蛋白的变化,并测定血清刺激后的单层内皮细胞通透性的变化.结果 和正常潮气量机械通气相比,大潮气量机械通气大鼠血清中的炎性介质可以导致内皮细胞周边肌动蛋白带消失,细胞中央出现明显应力纤维,细胞骨架重排,而大潮气量机械通气开始时注射乌司他丁的大鼠血清对内皮细胞骨架重排影响减轻,3组机械通气后的大鼠血清作用于单层内皮细胞后,内皮细胞通透系数变化百分比(Pa%)分别为(6.95±1.66)%,(27.50±7.77)%,(17.71±4.66)%.结论 大潮气量机械通气大鼠血清中的炎性介质可诱导内皮细胞骨架中重组,应力纤维形成,增加其通透性,而乌司他丁可减轻大潮气量大鼠血清中炎性介质对内皮细胞骨架的影响,应力纤维生成减少,改善了内皮细胞的通透性.

Effects of serum of rats with ventilator-induced lung injury on endothelial cell permeability and its mechanism

OBJECTIVE: To investigate the effects of inflammatory mediators in the serum of rats with ventilator-induced lung injury (VILI) on endothelial cellular cytoskeleton and monolayer cellular permeability and explore the molecular mechanism of VILI-induced lung edema. METHODS: Thirty healthy male SD rats were divided into 3 groups, namely group A with normal tidal volume ventilation, group B with high tidal volume ventilation and group C with high tidal volume ventilation plus ulinastatin treatment. The serum was collected from each rat after ventilation and added into endothelial cell line ECV-304 culture medium, and 2 h later the changes of F-actin and cell permeability were observed. RESULTS: Compared to sera from rats with normal tidal volume ventilation, the sera of rats with high tidal volume ventilation caused obvious reorganization of actin cytoskeleton with weakened fluorescent intensity at the peripheral filament bands and formation of long and thick stress fibers in the center, which resulted in endothelial contraction and increased cell permeability. Pretreatment with ulinastatin could lessen these changes significantly. The percentage in change of permeability coefficient (Ppa%) after stimulation with the sera of rats in groups A, B and C was (6.95+/-1.66)%, (27.50+/-7.77)%, and (17.71+/-4.66)%, respectively, showing statistically significant differences (P<0.05). CONCLUSION: The pro-inflammatory mediators in the serum of rats with high tidal volume ventilation increases endothelial cell permeability by reorganizing actin cytoskeleton, and pretreatment with ulinastatin can lessen the hyperpermeability by inhibiting multiple pro-inflammatory mediators.