目的:探讨高压氧(HBO)对大鼠局灶性脑缺血再灌注环加氧酶-1(COX-1)、环加氧酶-2(COX-2)mRNA的表达及血脑屏障(BBB)通透性的影响.方法:160只Wister大鼠随机分为A、B、C、D 4组各40只.成功制备为局灶性脑缺血再灌注大鼠模型,术后C、D组于2、9、11、45及69 h点均行0.25 MPa HBO治疗.采用逆转录多聚酶链反应(RT-PCR)法及比色法分别检测大鼠4、11、23、48及72 h点脑组织中COX-1、COX-2mRNA的表达及伊文思蓝(EB)的浓度.结果:与A、C组比较,B、D组各时间点COX-1mRNA的表达差异无统计学意义;而COX-2mRNA的表达及EB的浓度在11～72 h点组明显高于A、C组(P<0.05,0.01).结论:HBO具有降低脑缺血再灌注过程中COX-2mRNA的表达,对血脑屏障具有保护作用,而对COX-1mRNA的表达作用不明显.%Objective: To investigate the effects of hyperbaric oxygen (HBO) on expressions of cyclooxygenase (COX) in the brain tissues and blood brain barrier (BBB) after local cerebral ischemia-reperfusion in rats. Methods:480 Wistsr rats were randomly divided into 4 groups: sham-operation group, cerebral ischemia-reperfusion (IR)group , HBO group, HBOtcerebral ischemia-reperfusion (HBO+IR) group. The model of focal cerebral ischemiareperfusion injury was induced by middle cerebral artery occlusion (MCAO), 0. 25 MPa (ATA) HBO was applied 5 times during the reperfusion period, and 2％ Evens blue (EB) was injected into tail veins one h before the animals were killed. The expression of COX mRNA and the contents of EB were determined by RT-PCR and spectrophotometer. Results: There was no significant difference in the expression of COX-1 mRNA between IR group and sham-operation group. COX-2 mRNA expression level and the contents of EB were significantly increased in IR group as compared with the sham-operation group (P＜0.05). The expression levels of COX-1 and COX-2 mRNA and the contents of EB in HBO group were similar to those in the sham-operation group. The expression of COX-2 mRNA and the contents of EB group were significantly decreased as compared with IR group (P＜0.01), but there was no significant difference in the expression level of COX-1 mRNA between HBO+IR group and IR group. Conclusion: HBO can reduce the expression of COX-2 mRNA and protect the permeability of BBB during cerebral ischemia-reperfusion, but has no obvious effects on the COX-1 mRNA expression.
展开▼
