不同血氧饱和度影响主肺动脉压力变化的离体血管模型研究

摘要

目的:建立不同血氧饱和度影响主肺动脉压力变化的离体模型,为进一步探索肺动脉高压机制提供研究平台.方法:取新西兰大耳白兔20只,随机选取5只作为正常对照组.其余15只分离肺动脉后将血管置于培养液中,并接入体外循环系统;以新鲜肝素化兔血灌流培养48 h,灌注压力维持40 mmHg(1 mmHg=0.133 kPa);期间通过调节膜肺给氧量控制血氧饱和度,建立3个模型组(n=5):高饱和度组(90％～100％)、中饱和度组(65％～75％)、低饱和度组(40％～50％).转流结束后获取离体血管和正常对照组兔肺血管行病理形态分析、肺动脉组织IPP6.0定量分析以及匀浆一氧化氮含量分析比较.结果:3个模型组转机时间均达到48 h,压力稳定控制在40 mmHg,血氧饱和度由高到低分别为(97.94±1.01)％、(72.14±12.85)％、(43.83±8.71)％(P<0.05).病理分析结果显示:与正常对照组兔肺动脉相比,3个模型组离体培养的肺动脉管壁均明显增厚;随着血氧饱和度降低,3个模型组离体培养的肺动脉弹力纤维逐渐增多、增粗,差异均有统计学意义(P<0.05).结论:本实验建立了不同血氧饱和度影响主肺动脉压力变化的离体血管模型.%Objective: To establish an in vitro vascular model to study the impact of different blood oxygen (O2) saturation on main pulmonary artery pressure changes in order to further explore the mechanism of pulmonary hypertension. Methods: 20 New Zealand white rabbits were randomly divided into 4 groups: Normal control group and 3 experimental groups as High O2 (90％-100％)saturation group, Middle O2 (65％-75％)saturation group and Low O2 (40％-50％) saturation group, n=5 in each group. The in vitro pulmonary artery segments were treated with fresh heparinized rabbit blood and connected to extracorporeal circulation system for 48h at perfusion pressure at 40 mmHg; the condition of O2 saturation was regulated by membrane oxygenator. Pathological morphology was compared among different groups. Results:The bypass time in all 3 groups was 48h and the pressure was stably controlled at 40 mmHg. Blood O2 contents in High O2 saturation group, Middle O2 saturation group and Low O2 saturation group were (97.94±1.01) ％, (72.14±12.85) ％and (43.83±8.71) ％ respectively, P<0.05. Pathological analysis indicated that compared with Normal control group, 3 experimental groups had increased thickness in pulmonary artery wall; upon O2 saturation decreasing, the elastic fibers in pulmonary artery became increasing and more thickening accordingly. Conclusion: We established an in vitro vascular model to study the impact of different blood O2 saturation on main pulmonary artery pressure changes in experimental rabbits.