高压氧对脑缺血再灌注小鼠明胶酶、一氧化氮合酶及血脑屏障的影响

目的:通过检测脑缺血再灌注小鼠明胶酶A(MMP－2)、明胶酶B(MMP－9)及一氧化氮合酶(NOS)活性,探讨高压氧(HBO)对脑缺血再灌注小鼠明胶酶、NOS及血脑屏障(BBB)通透性的影响。方法:复制脑缺血再灌注模型,并于再灌注期间经0.25MPaHBO治疗5次,采用明胶酶谱分析法及比色法,检测脑组织海马区明胶酶及NOS的活性,同时经尾静脉注射2%伊文思兰(EB),检测脑组织EB含量。结果:脑缺血再灌注后明胶酶(A、B)活性增加,HBO+脑缺血再灌注组明胶酶B(MMP－9)活性明显低于脑缺血再灌注组;而HBO对明胶酶A(MMP－2)作用不显著。脑缺血再灌注后NOS活性增加,HBO+脑缺血再灌注组NOS含量显著低于脑缺血再灌注组(P＜0.01)。脑组织EB含量以再灌注4h最高,11h、23h、48h、72h脑组织EB含量逐渐减少。高压氧+脑缺血再灌注组脑组织EB含量明显低于脑缺血再灌注组(P＜0.05,P＜0.01)。结论:高压氧具有降低脑缺血再灌注小鼠明胶酶B及NOS活性,降低血脑屏障的通透性的作用。

Effect of hyperbaric oxygen on gelatinase, nitric oxide synthase and the permeability of brain blood barrier in cerebral ischemia-reperfusion mice

AIM:To investigate the effect of hyperbaric oxygen (HBO) on gelatinase,nitric oxide synthase and the permeability of brain blood barrier(BBB) in ischemia-reperfusion(I/R) mice.METHODS:Using cerebral I/R models, during the reperfusion period, 0.25 MPa (ATA) HBO were applied 5 times. matrix metalloproteinase(MMP)-2,9, nitric oxide synthase(NOS) and evans blue (EB) in brain were measured.RESULTS:①HBO had significanty effect on MMP-9, but had little effect on MMP-2. ② HBO decreased the activity of NOS.③ The maxium amount of EB in IR group was at 4 hours after reperfusion and gradually decreased at 11 h, 23 h,48 h, 72 h.CONCLUSION:HBO may decrease the activities of MMP-9,NOS and the permeability of BBB in cerebral ischemia-reperfusion mice.