β-淀粉样蛋白增加基底前脑神经元对谷氨酸的易感性

Study on beta amyloid protein enhancing the sensibility of primary cultured basal forebrain neuron to glutamic acid

目的探讨β-淀粉样蛋白25-35(Aβ25-35)与谷氨酸(Glu)联合应用,对原代培养的大鼠基底前脑神经元的作用。方法原代培养大鼠基底前脑神经元,应用形态学、MTT法结合ChAT免疫组织化学染色,分别观察Aβ25-35与Glu联合应用,对原代培养的基底前脑神经元存活率、形态学及ChAT免疫反应阳性神经元的影响。结果将100 nmol/L、1μmol/L Aβ分别和20μmol/L Glu联合用于培养的基底前脑神经元,在倒置显微镜下观察,细胞表面粗糙,立体感减弱,胞浆中出现深色颗粒,细胞肿胀或收缩;尼氏染色显示尼氏体减少;MTT检测显示神经元存活率明显下降,100nmol/L Aβ+20μmol/L Glu组与100 nmol/L Aβ组间,1μmol/L Aβ+20μmol/L Glu组与1μmol/L Aβ组间比较均具有统计学差异(P<0.05);ChAT免疫阳性神经元的灰度和截面积均减小。结论Aβ25-35可增加神经元对Glu神经毒性作用的敏感性,表明Glu在阿尔茨海默病发病中起着非常关键的作用。

Objective To study the effects of Aβ025-35 and glutamic acid on primary cultured rat basal forebrain neurons. Methods Morphological study, MTT test, and ChAT immunohistochemistry method were adopted to observe and analyze the effects of Aβ25-35 and glutamic acid on morphology, survival rate, choline acetylase positive neurons of rat basal forebrain, Results 100 nmol/L and 20μmol/L glutamic acid either 1μmol/L Aβ25-35 and 20μmol/L glutamic acid were added to medium, respectively, under inverted microscope, the surface of neurons were rough, stereognosis of neurons died down, the dark granules-like appeared in perikaryon; Nissl bodys decreased, the neurons were swollen or contracted in Nissl staining;the result of MTT test showed that the survival rate of neurons was obviously decreased. There were differences between 100 nmol/L Aβ ＋20μmol/L Glu group and 100 nmol/L Aβ group, 1μmol/L Aβ ＋ 20μmol/L Glu group and 1 μmol/L Aβ （ P〈0.05）, respectively, The optic density and area of ChAT positive neurons was deminished. Conclusion Aβ25-35 can enhance the sensibility of primary cultured neurons of rat basal forebrain to glutamic acid, Glutamic acid play a key role in the pathological process of Alzheimer＇s disease.