白介素18在脂多糖致大鼠脑水肿中的表达

Expression of interleukin 18 in brain edema induced by lipopolysaccharide in rats

目的探讨白介素18(IL-18)在脂多糖(LPS)致大鼠脑水肿发病过程中的表达及纳络酮对其干预作用。方法SD大鼠84只,对照组(NS组)28只,0.2mL生理盐水颈内动脉注射;内毒素组(LPS组)28只,颈内动脉注射LPS200μg;纳络酮治疗组(NAL组),28只,颈内动脉注射LPS后10min、1、2、6、12h及处死前2h腹腔注射纳络酮1mg/kg。于不同时间点测定脑组织匀浆IL-18的含量。干湿法测定脑组织含水量,甲酰胺法测定伊文思兰(EB)含量。结果LPS组脑组织含水量和EB含量显著高于NS组(P<0.01)。NAL组脑组织含水量和EB含量显著低于LPS组(P<0.01),但仍较NS组高(P<0.01)。LPS组IL-18的含量显著高于NS组(P<0.01)。NAL组IL-18在4、6、12h时表达降低,与LPS组比较差异显著(P<0.05或P<0.01),但在48h时差异无显著性(P>0.05)。LPS组脑组织含水量和EB含量呈正相关(r=0.743,P<0.01),IL-18含量与含水量呈正相关(r=0.616,P<0.01),IL-18含量与EB含量呈正相关(r=0.497,P<0.01)。结论IL-18参与了脑水肿的发生发展,纳络酮可以抑制IL-18的生成,减轻脑水肿。

Objective To study the expression of interleukin 18 （IL-18） and the interfering effects of naloxone in the brain edema induced by lipopolysaccharide （LPS） in rats. Methods Total of 84 SD rats were randomly divided into three groups： normal saline group （NS group, n = 28）, in which rat was injected with 0.2 mL normal saline by carotid; LPS group （LPS group, n = 28）, in which rat was injected with applied 200 μg LPS by carotid; naloxone interfering group （NAL group, n = 28）, in which rat was injected intraperitoneally with 1 mg/kg naloxone at 10 min, 1, 2, 6, 12 h, and 2 h before decapitation following LPS injection. The contents of IL-18 and even blue （EB） in brain tissue were detected at different time points. The brain water content was measured by drying method. Results The content of water and EB in LPS group were significantly higher than that in NS group （P 〈 0.01）. In NAL group, the content of water and EB were significantly lower than that in LPS group （P 〈 0.01）, but higher than that in NS group （P 〈 0.01）. IL-18 content in LPS group was significantly higher than that in NS groups （P 〈 0.01）. At 4, 6, and 12 h, IL-18 content in LPS group was significantly higher than that in NAL groups （P 〈 0.05 or P 〈 0.01）, but at 24 h, no significant difference was found in the two groups. In LPS group, water content and EB content were positively correlated （r = 0.743, P 〈 0.01）; IL-18 content and water content were positively correlated （r = 0.616, P 〈 0.01）; IL-18 content and EB content were positively correlated （r = 0.497, P 〈 0.01）. Conclusion IL-18 may participate in the onset and development of brain edema induced by LPS. NAL has therapeutic effect on the brain edema by affecting the production of IL-18.