不同压力高压氧促进大脑中动脉闭塞大鼠梗死周边区细胞增殖的研究

Hyperbaric oxygen therapy promote the proliferation in peri-infarct region of cerebral artery occlusion rats

目的比较延迟、连续给予不同压力(1.5ATA和2.5ATA)的高压氧治疗(HBOT),对永久性大脑中动脉闭塞(pMCAO)大鼠梗死周边区细胞增殖的影响。方法雄性SD大鼠80只,分为假手术组、空气组(pMCAO加空气),1.5ATA组(pMCAO加1.5ATA HBOT)和2.5ATA组(pMCAO加2.5ATA HBOT),每组20只。采用大脑中动脉线栓法建立永久性大鼠缺血模型。于术后48h开始高压氧治疗,连续10d,每天1h。于术后28d采用改良Garcia评分法和平衡能力测试评估神经功能,尼氏染色观察脑梗死面积和细胞增殖情况,Western blot法检测环磷酸腺苷反应单元结合蛋白(CREB)在大鼠脑梗死区的表达情况。结果术后28d各组的改良Garcia评分分别为假手术组18分,空气组(13.25±0.57)分,1.5ATA组(13.80±0.62)分和2.5ATA组(16.32±0.35)分。平衡能力测试各组得分为假手术组3分,空气组(0.98±0.33)分,1.5ATA组(1.30±0.52)分和2.5ATA组(2.25±0.35)分。各组的梗死率分别为假手术组0,空气组(33.15±2.66)%,1.5ATA组(31.20±3.25)%和2.5ATA组(13.58±2.15)%。2.5ATA HBOT组与空气组比较神经功能评分有明显改善,梗死面积减少,梗死周边区域的细胞增殖增加,且该区域CREB的表达上调(P<0.05);而1.5ATA HBOT组与空气组比较,上述指标差异无统计学意义(P>0.05)。结论 2.5ATA高压氧的神经保护作用可能与CREB上调促进梗死周边区细胞增殖有关。

Objective To explore the effect of different pressure（1.5ATA and 2.5ATA）of hyperbaric oxygen therapy（HBOT）on proliferation in the permanent middle cerebral artery occlusion（pMCAO）rats.Methods Male SD rats were randomly divided into 4groups,including sham＋air group,pMCAO＋air group,pMCAO＋1.5 ATA HBOT（1.5 ATA）group and pMCAO＋HBOT（2.5ATA）group（n=20）.HBOT（100% O2）was started 48 hafter pMCAO,1hdaily over 10 consecutive days.Garcia score and beam balance test were performed after 28 dof pMCAO to evaluate neurological deficits.The infarct size and cell prolifereation were analyzed by immunohistochemistry.Western blot was used to detect the level of cAMP response element-binding protein（CREB）.Results Garcia scores were 18 in sham＋air group,13.25±0.57 in air group,13.80±0.62 in the 1.5ATA group and 16.32±0.35 in the 2.5ATA group.scores of beam balance test were 3in sham＋air group,0.98±0.33 in the air group,1.30±0.52 in 1.5ATA group and 2.25±0.35 in 2.5ATA group.infarct ratios were 0in sham＋air group,（33.15±2.66）%in air group,（31.20±3.25）%in 1.5ATA group and（13.58±2.15）%in 2.5ATA group.Compared to the air group,2.5ATA group effectively reduced the mortality and infarct size.Also it increased the peri-infarct region cell proliferation with up-regulated expression of CREB（P〈0.05）.Conclusion 2.5ATA HBTO may promote the cell proliferation in the peri-infarct region after pMCAO through CREB expression.