β-淀粉样多肽诱导神经元凋亡和氧化应激机制的实验观察

Experimental Observation on Neuronal Apoptosis Induced by β-amyloid Peptide and Its Mechanism of Oxidative Stress

目的 :观察 β 淀粉样多肽 (Aβ)的神经毒性作用及其氧化应激机制。 方法 :取 2 0只大鼠 ,每组 10只 ,实验组双侧海马内注射Aβ2 5 35,对照组注射生理盐水 ;HE染色和TUNEL方法检测凋亡 ;另一侧海马组织制成脑匀浆 ,比色法测定丙二醛 (MDA)、还原型谷光甘肽 (GSH)、过氧化氢酶 (CAT)和谷光甘肽过氧化物酶 (GSH Px)活力 ;统计学分析用t检验。结果 :HE染色和TUNEL法检测实验组可见散在凋亡神经元。与对照组相比 ,实验组MDA水平增加 ,GSH水平降低 ,CAT和GSH Px活力降低。结论 :Aβ可诱导神经元凋亡 。

Aim:To observe the neurotoxic effect and mechanism of oxidative stress induced by β-amyloid peptide (Aβ) Methods:In experimental group, Aβ 25-35 was microinjected into hippocampus of rats; in control group, 0.9% NS instead of Aβ. The paraffin section from one side of hippocampus was stained by HE and the neuronal apoptosis was detected with TUNEL method. The MDA, GSH, GSH-Px and CAT from other side of hippocampal homogenate were measured by chromatometry. The statistical analysis was used by t -test. Results:The diffused karyopyknosis of neurons in HE staining and the positive neurons by TUNEl method in hippocampus were found. Aβ increased the level of MDA, decreased the level of GSH and the activity of GSH-PX and CAT.Conclusion:Aβ was able to induce neuronal apoptosis, the neurotoxic effect was mediated by oxidative stress.