【摘要】 目的　观察金属硫蛋白对 β 淀粉样蛋白 (Aβ)所致的氧化应激 (OS)的影响。 方法　在成年大鼠侧脑室内注入聚集态 β 淀粉样蛋白1 5nmol后 ,随即在实验组用微渗泵持续注射不同剂量和种类的金属硫蛋白 (metallothionein ,MT) ,对照组金属硫蛋白用生理盐水代替。 5d后测定大鼠海马几种氧化 抗氧化指标以及与认知能力有关的乙酰胆碱酯酶 (AChE)的活力。结果　相对于对照组 ,低浓度MT2 (0 0 5g/L)和高低 (1 0和0 0 5g/L)两种浓度的MT3均可导致GSH水平升高 ,低浓度MT3还可以使海马中GSH Px的活性增强。高浓度MT3不但对抗氧化酶无影响 ,组织中MDA含量反而升高。结论　MT脑室内注射可以提高鼠脑的抗氧化能力 ,但MT3的作用效果与浓度有关。相同浓度的MT2和MT3后者使动物抗氧化能力提高的作用更强。更多还原

【Abstract】 Objective To investigate the role of metallothionein (MT) in the oxidative stress (OS) induced by β amyloid peptide (Aβ) in rat brain.Methods In the experimental group, a single intracerebroventricular administration of aggregated Aβ (25 35) 15 nmol was followed by MT continual injection of different type and concentration using ALZET osmotic pump. In the control group, MT was replaced by saline. On the 5 postoperative day, several parameters of oxidative antioxidative system as well as activities of acetyl cholinesterase (AChE), which is known for relating to cognitive abilities, in hippocampus were measured. Results Compared with the control group, the MT2 of low concentration(0.05 g/L)and MT3 of either high(1.0 g/L)or low concentration (0.05 g/L)could increase the GSH level, which is a powerful antioxidant. The MT3 of low concentration also could improve the GSH PX activity in hippocampus, but no effects were found with the MT3 of high concentration. On the contrary, the MDA level in rat brain increased after injection of high concentration MT3 injection. Conclusions MT can improve the antioxidative ability of rat brain in a concentration dependent manner. For the same concentration, the antioxidative ability of MT3 is stronger than that of MT2.更多还原