摘要目的 评价氨基氧乙酸对大鼠局灶性脑缺血损伤的影响.方法 健康雄性SD大鼠80只,体重250～280 g,月龄2.5个月,采用随机数字表法,将其随机分为5组(n＝16):假手术组(S组)、脑缺血组(Ⅰ组)、低、中、高剂量氨基氧乙酸组(AL组、AM组和AH组).Ⅰ组、AL组、AM组和AH组采用线栓法(阻塞大脑中动脉)制备大鼠局灶性脑缺血损伤模型.AL组、AM组和AH组于缺血3h时分别腹腔注射氨基氧乙酸25、50、100 μmol/kg,S组和Ⅰ组给予等容量生理盐水1ml/kg.每组于给予氨基氧乙酸后21 h时取8只大鼠,进行神经功能缺陷评分,然后处死大鼠,取脑组织,分离皮层、海马、纹状体,测定胱硫醚-β合酶( CBS)活性.每组于给予氨基氧乙酸后21 h时处死另外8只大鼠,取脑组织,测定脑梗死体积.结果 与S组比较,Ⅰ组神经功能缺陷评分、皮层和海马CBS活性升高,脑梗死体积扩大(P<0.05),纹状体CBS活性差异无统计学意义(P＞0.05)；与Ⅰ组比较,AM组和AH组神经功能缺陷评分、皮层和海马CBS活性降低,脑梗死体积缩小,纹状体CBS活性差异无统计学意义(P＞0.05)；AL组上述指标差异无统计学意义(P＞0.05).结论 氨基氧乙酸可减轻大鼠局灶性脑缺血损伤,其机制与抑制CBS活性,减少H2S生成有关.

abstractsObjective To evaluate the effect of aminooxyacetic acid on focal cerebral ischemia injury in rats.Methods Eighty healthy male SD rats aged 2.5 month weighing 250-280 g were randomly divided into five groups( n ＝ 16 each):sham operation group(group S),cerebral ischemia group(group Ⅰ),aminooxoacetic acid low,medium and high dose groups(groups AL,AM and AH ).Focal cerebral ischemia was induced by occlusion of middle cerebral artery using a nylon thread with rounding tip which was inserted into right internal carotid artery in groups I,AL,AM and AH.Intraperitoneal amincoxoacetic acid 25,50 and 100 μmol/kg were administered at 3 h of ischemia in groups AL,AM and AH respectively,while equal volume of normal saline 1 ml/kg were injected in groups S and I.Neurological function was assessed and scored (0＝ no deficit,4＝ unable to move,unconscious) in 8 rats at 21 h after aminooxyacetic acid administration in each group.The animals were then sacrificed and the brains were removed for determination of the cystathionine beta-synthase (CBS) activities in cortex,hippocampus and striatum corpora.The other eight rats of each group were sacrificed at 21 h after amincoxoacetic acid administration for determination of the cerebral infarct volume.Results Compared with group S,the neurological deficit scores and the CBS activities in cortex and hippocampus were significantly increased,the infarct volumes were significantly enlarged in group Ⅰ ( P < 0.05).Compared with group Ⅰ,the neurological deficit scores and the CBS activities in cortex and hippocampus were significantly decreased,the cerebral infarct volumes were significantly reduced in groups AM and AH (P < 0.05).There was no significant difference in the above-mentioned variables between groups AL and Ⅰ.Conclusion Aminooxoacetic acid can reduce focal cerebral ischemia injury by decreasing CBS activity and reducing H2 S production in rats.