芦荟减阻剂对烧伤休克大鼠微循环的影响

Effects of Drag-reducing polymer derived from Aloe vera on microcirculation in burn rats

目的:探讨芦荟减阻剂对大鼠40%体表面积深Ⅱ度烧伤休克模型微循环的影响。方法:SD大鼠随机分为3组:对照组、减阻剂组及盐水组(烫伤后5 min给予减阻剂或者盐水进行补液复苏)。检测烧伤休克后24 h肺湿干重比(W/D)、病理及动脉血气;活体微循环观测技术观察烧伤休克后脊斜肌微动脉红细胞流速;观察动物的存活时间。结果:与对照组比较,盐水组肺组织W/D增加(P<0.05),PO2降低、Lac增高(P<0.05或P<0.01),脊斜肌微动脉红细胞流速明显降低(P<0.01),HE染色见大量中性粒细胞浸润;与盐水组比较,减阻剂组肺组织W/D明显降低(P<0.05),PO2增加、Lac降低(P<0.05或P<0.01),HE染色中性粒细胞浸润减少,脊斜肌微动脉红细胞流速明显增高(P<0.01)并且减阻剂治疗组大鼠生存时间显著延长(P<0.05)。结论:芦荟减阻剂明显改善烧伤休克后肺损伤,其机制可能是通过改善烧伤休克后微循环。

Objective To investigate the effects of drag-reducing polymers on microcirculation in 40% total body surface area burn-injured rats. Methods SD rats were randomized into control group, drag-reducing polymer（DRPs） group and normal saline（NS） group（5 minutes after scald, drag-reducing polymer or saline was injected for fluid resuscitation）. Wet dry weigh ratio of lung, histopathologic changes and arterial blood gas at 24 hour were respectively measured by wet dry weigh ratio method, hematoxylin-eosin（HE） staining and arterial blood gas analysis. The velocity of flow of red cell in oblique ridge and the survival time of burn-injured rats were observed.Results Compared with control group, rats in NS group exhibit significant lung injury characterized by a high W /D（P〈0.01）, accumulation of a large number of neutrophils in HE stain, low partial pressure of oxygen（PO2）and high lactate（Lac）（P〈0.05 or P〈0.01） in arterial blood. Compared with the NS group, DRPs treatment rats exhibit significantly reduced lung injury characterized by W / D reducing（P〈0.05）, the reduction of neutrophil infiltration, increased PO2, decreased Lac（P〈0.05, P〈0.01）. In addition, DRPs treatment obviously increases the burn-induced low velocity of flow of red cell in oblique ridge（P〈0.01）. Moreover, the survival time of burnedrats can be improved by DRPs treatment（P〈0.05）. Conclusion DRPs ameliorates burn-induced acute lung injury, the mechanism may be through improving the burn-induced microcirculation disorders.