异氟醚后处理对新生大鼠缺血缺氧性脑损伤的保护作用

 目的 探讨不同浓度异氟醚后处理对新生大鼠缺血缺氧性脑损伤的影响。 方法 7 d龄新生SD大鼠125只随机分为5组(n=25):假手术组（Ⅰ组）、脑缺血缺氧组（Ⅱ组）、1%异氟醚后处理组（Ⅲ组）、1.5%异氟醚后处理组（Ⅳ组）和2%异氟醚后处理组（Ⅴ组）。除Ⅰ组外，其余各组均行左颈总动脉结扎和8%低氧2 h处理，制成新生大鼠缺血缺氧性脑损伤模型。Ⅲ、Ⅳ和Ⅴ组脑损伤后即刻分别吸入1%、1.5%和2%异氟醚30 min。于脑损伤后7 d测各新生鼠的左右大脑半球质量，并行脑组织损伤病理检测。 结果 与Ⅰ组相比，其余4组的左/右大脑半球质量比及丘脑腹后内侧核和后扣带回皮层左/右侧神经元密度的比值降低(P<0.05)；与Ⅱ组相比，Ⅳ和Ⅴ组左/右大脑半球质量比及丘脑腹后内侧核和后扣带回皮层左/右侧神经元密度比降低的程度减轻(P<0.05)。 结论 1.5%和2%异氟醚后处理能够减轻新生大鼠缺血缺氧性脑损伤程度。

Protective Effect of Isoflurane Postconditioning on Reducing Hypoxic-ischemic Brain Injury in Neonatal Rats

Objective To investigate the effects of different doses of isoflurane postconditioning on neonatal hypoxic/ischemic brain injury in rats.Methods 125 seven-day-old SD rats were randomly divided into 5 groups(n =25):groupⅠ:sham surgery,the pups of other four groups had left common carotid arterial ligation followed by hypoxia with 8% oxygen for 2 h at 37 °C.Isoflurane postconditioning with 1%(group Ⅲ),1.5%(group Ⅳ) or 2%(group Ⅴ) isoflurane for 30 min was performed immediately after the brain hypoxia/ischemia.The weight ratio,neuronal density ratio in the ventral posteromedial thalamic nucleus and the retrosplenial granular cortex of left to right cerebral hemispheres at 7 days after the brain hypoxia/ischemia was calculated.Results Compared with control(groupⅠ),the weight ratio and neuronal density ratio in the ventral posteromedial thalamic nucleus and in the retrosplenial granular cortex of left/right cerebral hemispheres in other four groups decreased(P < 0.05).Compared with group Ⅱ,the decreasing level in the weight ratio and neuronal density ratio in the ventral posteromedial thalamic nucleus and in the retrosplenial granular cortex of left/right cerebral hemispheres induced by hypoxia/ischemia in group Ⅳ and Ⅴ reduced(P < 0.05).Conclusion 1.5% and 2% isoflurane postconditioning induced neuroprotection in neonatal rats of brain hypoxia and ischemia injury.