大鼠高碳酸血症模型的复制及其病理生理变化的实验研究

Experimental study on setting up hypercapnic model and its pathophysiological changes in rats

目的 :复制大鼠高碳酸血症模型并探讨模型动物的某些病理生理改变。方法 :给大鼠呼吸高浓度二氧化碳气体 (8%CO2 ,2 1%O2 ,71%N2 ) ,每天 7h ,连续 2 8d。对比观察对照组 (A组 )和高碳酸血症组 (B组 )的各项指标变化。结果 :B组PaCO2 [(5 5 .90± 3.34 )mmHg],血浆、肺组织和右心室过氧化脂质 (LPO)显著高于A组 (P<0 .0 5 ) ;血红细胞、肺及右心室组织超氧化物歧化酶 (SOD)以及动脉血pH显著低于A组 (P <0 .0 5 )。平均右心房压( Rap)、平均右心室压 ( Rvp)和平均肺动脉压 ( Pap)两组间无显著性差异 ,但B组大鼠右心室重量明显高于A组 (P <0 .0 5 )。光镜下可见B组大鼠肺组织、右心室出现一系列损伤性改变。结论 :8%CO2 可以复制大鼠高碳酸血症模型。高浓度二氧化碳对机体具有一系列肯定的毒性致伤作用。临床上应用允许性高碳酸血症通气模式时应持高度慎重态度。

AIM: To reproduce hypercapnic models and approach some pathophysiological changes in rats. METHODS: The mixed gases of high concentrated carbon dioxide (8% CO 2, 21% O 2, 71% N 2) were given to wistar rats 7 hours a day for 28 days. The various indexes were compared between control group (group A) and hypercapnic group (group B). RESULTS: The PaCO 2 [(55.90±4.34) mmHg] and the lipid peroxides (LPO) contents in plasma, lung tissue and right ventricle were significantly higher in group B than those in group A ( P<0.05 ); while artery pH values (7.205±0.037) and superoxide dismutase (SOD) activities in erythrocytes, lung tissue and right ventricle were significantly decreased in group B compared with group A ( P<0.05 ). The weight of right ventricle was significantly heavier than that of group A ( P<0.05 ). There were no significant differences were found in mean right artial pressure (ap), mean right ventricle pressure (vp) and mean pulmonary artery pressure (ap) between both groups.CONCLUSION: Hypercapnic model can be reproduced with 8% CO 2 mixed gases in rats. High concentration of CO 2 can cause a series of positively toxic injuries to the body. Care should be seriously taken when using permissive hypercapnic ventilation in the clinic. [