甲基泼尼松龙对油酸型急性肺损伤兔干预作用的实验研究

目的探讨甲基泼尼松龙(MP)对油酸致兔急性肺损伤的治疗作用,并进一步探讨MP大剂量和中小剂量在治疗中的疗效差别。方法随机将32只日本大耳白兔分成4组:正常组、油酸模型组、MP1组(MP中小剂量)和MP2组(MP大剂量)。模型组选定0、30、60、90、120min,其余各组选定0、30、60、90、120、180、240、300、360min,分别测量每只兔动脉血气和血清中的超氧歧化酶(SOD)、诱导型一氧化氮合酶(iNOS)的含量。各组在实验120min观察肺组织超微结构变化。结果(1)MP1组与MP2组肺组织超微结构变化均较模型组轻。MP2组120min时肺组织超微结构变化较MP1组轻。(2)MP1组与MP2组0~120minPaO2、SOD均较模型组显著增加(P<0·05),iNOS较模型组显著减少(P<0·05),且MP1组和MP2组组间上述指标差异均有显著性意义(P<0·05),MP2组更接近正常。MP1组与MP2组120~360min上述指标变化相反,两组间差异有显著性意义(P<0·05),MP1组更接近正常。结论MP对油酸致兔急性肺损伤有明显的疗效,120min前MP大剂量好于MP中小剂量,而120min后MP中小剂量疗效要好于MP大剂量。

Therapeutic Effects of Methylprednisolone on Acute Lung Injury Induced by Oleic Acid in Rabbits

Objective To observe the effects of Methylprednisolone (MP) at large or medium and small dosage on acute lung injury induced by oleic acid in rabbits and to compare difference of curative effects of different dosage.Methods Totally 32 rabbits were randomly divided into 4 groups (n=8); normal group, model group, MP1 group (MP at medium and small dosage) and MP2 group (MP at large dosage). The PaO_2 and the contents of SOD and iNOS in blood serum were measured in model group at 0, 30, 60, 90, 120 min; and in the rest groups at 0, 30, 60, 90, 120, 180, 240, 300, 360 min. The ultrastructure of lung tissues were observed in all groups at 120 min.Results (1) Ultrastructural change of lung in MP1 group and MP2 group were slighter than that in the model group at 120 min, and the change in MP2 group was slighter than that in MP1 group. (2)From 0 min to 120 min of the experiment, PaO_2 and the content of serum SOD obviously increased (P<0.05) and the content of serum iNOS obviously increased (P<0.05) in the MP1 group and MP2 group than those in the model group, and with a significant difference between MP1 group and MP2 group (P<0.05), and MP2 group tending to be normal. From 120 min to 360 min of the experiment the changes of the above indexes in MP1 group were opposite to those in MP2 group, with a significant difference (P<0.01), and MP1 group tending to be normal.Conclusion Methylprednisolone can reduce acute lung injury induced by oleic acid, and the effect at large dosage was better than that at medium and small dosage before 120 min, but after 120 min the change was opposite.