缺氧对大鼠白细胞粘弹性的影响

Effects of hypoxia on viscoelastic properties of polymorphonuclear leukocyte of rats

目的研究急、慢性缺氧对中性粒细胞粘弹性的影响。方法低压舱模拟高原复制缺氧模型,成年Wistar大鼠15只,随机分为常氧组、急性缺氧组(5000m减压3d)和慢性缺氧组(5000m减压30d)。微管吸吮技术分析粒细胞粘弹性变化,标准线性固体模型拟合结果。结果常氧组粒细胞弹性模量K1为(39.52±16.06)Pa,K2为(148.85±9.06)Pa,粘性系数μ为(2.28±1.11)Pa.s;急、慢性缺氧组各参数均显著增大(P<0.05),K1为(86.66±26.84)Pa和(179.61±26.31)Pa,K2为(399.89±22.03)Pa和(472.12±30.36)Pa,μ为(4.23±1.82)Pa.s和(9.21±2.65)Pa.s;急性缺氧初始变形长度、最大变形长度和时间常数较对照组显著减小(P<0.05),但慢性缺氧组时间常数较对照组已无明显差异(P>0.05)。结论急、慢性缺氧对粒细胞生物力学特性有明显影响,表现为细胞膜刚性增大,细胞变形性下降。

Objective To explore the effects of acute or chronic hypoxia on the viscoelastic properties of polymorphonuclear leukocyte （PMN） of rats. Methods Hypobaric chamber was used to simulate high altitude condition. Fifteen adult Wistar rats were randomized into 3 groups： control, acute hypoxia （5 000 m for 3 d） and chronic hypoxia （5 000 m for 30 d）. Micropipette aspiration technique was used to evaluate the biomechanical properties of PMNs of rats and the experimental results were fitted with a three-element standard linear solid model. Results The viscoelastic coefficients of PMNs in acute hypoxic condition [ K1 = （ 86.66± 26. 84 ） Pa, K2 = （ 399.89± 22.03 ） Pa, μ = （4.23 ±1.82 ） Pa · s ] or those values in chronic hypoxic condition [K1 =（179.61 ±26.31） Pa, K2 = （472.12±30.36） Pa, K2= （9.21±2.65） Pa· s] were significantly higher than the corresponding value of PMNs in control（P 〈0.05） [K1= （39.52± 16.06） Pa,K2 = （ 148.85± 9. 06） Pa, μ = （2.28±1.11 ） Pa·s ]. Compared with the control, the initial strain, maximum strain and the time constant in acute hypoxia was obviously decreased （ P 〈 0. 05 ）, but the time constant in chronic hypoxia had no difference. Conclusion These results suggest that acute or chronic hypoxia has strong impact on the biomechanical properties of PMN, involving the increased rigidity of cell membrane and the decreased deformation of cell.