高压氧与甘露醇联合作用对不同时相肢体缺血再灌注损伤细胞凋亡与组织超微结构的影响

Combined effects of hyperbaric oxygen and mannitol on the apoptosis and ultramicrostructure changes of cells of limb ischemia and reperfusion injury of different phases in rats

目的:研究肢体缺血-再灌注损伤的发生和病理改变,探讨高压氧与甘露醇联合作用对不同时相肢体缺血再灌注大鼠的凋亡及组织超微结构的影响。方法:将204只SD大鼠随机分组,各组均持续缺血8h,分别行再灌注0、4、24、72h,连续5d经甘露醇和/或高压氧干预,制备石蜡切片检测大鼠肌肉组织中细胞凋亡相关基因Bax、Bcl-2的表达;以大鼠腓肠肌制备电镜标本,观察骨骼肌超微结构变化。结果:所有干预组较Control组在再灌注后4、24、72h3个时点Bax含量均显著降低;HBO组、甘露醇-HBO组较Control组在再灌注后4、24h2个时点Bcl-2均显著升高。甘露醇组较Control组在再灌注后4hBcl-2均显著升高。高压氧治疗后,骨骼肌细胞肿胀及炎性细胞浸润均较轻,微血管内几乎无微血栓形成,肌小节极少断裂,质膜较少破坏,少数线粒体肿胀,髓样结构形成。高压氧与甘露醇联合作用显著优于单用高压氧或甘露醇(P<0.05)。高压氧作用显著优于甘露醇作用(P<0.05)。结论:本实验应用甘露醇联合高压氧作用于不同时相缺血再灌注肢体,产生了较显著的保护作用。

Objective：To investigate the occurrence and pathological changes of the limb ischemia-reperfusion injury of different phases and the combined effects of hyperbaric oxygen and mannitol on the apoptosis and ultramicrostructure changes of rats.Methods：204 SD rats were randomly divided into various groups,underwent different phases of reperfusion after 8 hours of sustained ischemia,and treated with hyperbaric oxygen and/or mannitol for five days.The expression of cell poptosis-related gene Bax,and Bcl-2 was detected through the paraffin sections of rat skeletal muscle.Electron microscope was used to observe the ultramicrostructure changes of the gastrocnemius muscle under the effects of different interventions.Results：In all the intervention groups the Bax levels at 4 h,24 h,72 h after reperfusion were significantly less than in the control groups.In HBO and mannitol-HBO groups the Bcl-2 levels at 4 h,24 h were significantly higher than in the control groups.And in mannitol groups the Bcl-2 levels at 4h were significantly higher.In hyperbaric oxygen groups,the cellular swelling of skeletal muscle and the local cytokine response were significantly lower,almost without microvascular thrombosis in capillary vessel.The sarcomere was rarely collapsed,little plasma membrane was shattered,little mitochondrial swelled or changed into the myelinfigure.The combined effects of hyperbaric oxygen and mannitol were significantly better than single-use of hyperbaric oxygen or mannitol（P 〈0.01）.The role of hyperbaric oxygen was significantly better than mannitol（P〈0.05）.Conclusion：The combined effects of hyperbaric oxygen and mannitol has a more significant role in the protection against the limb ischemia and reperfusion of different phases.