摘要
β－淀粉样蛋白是老年斑的主要成分。为探讨其在老年性痴呆患者基底前脑胆碱能神经元选择性溃变中的作用，运用ＭＴＴ自动比色微量分析法、胆碱酯酶组织化学染色及细胞形态学分析方法，研究“老化”的淀粉样蛋白片段３１～３５对体外培养的海马和隔区神经元的作用。结果表明：培养４８ｈ，淀粉样蛋白对海马神经元有毒性作用，减少神经元的存活，呈剂量依赖关系。培养１４ｄ，淀粉样蛋白减少了胆碱能神经元的存活率，抑制突起的延伸，促使神经元胞体和近侧突起的分支增加。表明淀粉样蛋白对隔区胆碱能神经元具有减少存活、抑制突起延伸和促进突起不正常生长的毒性作用。
β amyloid peptide(Aβ) is an important component in senile plaque,that is one of the neuropathological features of Alzheimer disease (AD).In order to explore the effects of β amyloid peptide on the septal cholinergic neurons,which was lost in AD,AChE histochemistry and cellular morphological methods and a rapid automated colorimetric microassy were used.The results show that aged Aβ31～35 has the toxic effects on the hippocampal neuron and cholinergic neuron. The number of living neurons in hippocampal cultures was decreased in dose dependent for 48 hours.Aβ31～35 promotes sprouting of the proximal processes and some regions of cholinergic neurons in septal but inhibits the prolongation of new branch and main processes for culture 14 days.It is suggested that accumulation of Aβ fragments may have a relation with selective loss of septal cholinergic neurons and aberrantly sprouting of processes in senile plaque of AD.
基金
国家自然科学基金
美国中华医学基金会(CMB)资助
