McNeill T H, Koek L L, Haycock J W
Mech Ageing Dev. 1984 Mar;24(3):293-307. doi: 10.1016/0047-6374(84)90115-5.
Alterations in neurotransmitter systems of the basal ganglia have been postulated to contribute to the disruption of motor function and balance associated with aging. This study examined nigrostriatal (A9) and mesolimbic (A10) dopamine neurons for qualitative age-correlated changes using fluorescence histochemistry for catecholamines and immunocytochemical techniques for the catecholamine-synthesizing enzyme, tyrosine hydroxylase. Results from this study suggest that age-correlated morphological changes in A9 but not all A10 neurons in the midbrain are present in mature adult (10-month) C57BL/6NNia mice and show a progressive increase in severity until at least 30 months of age. These changes are characterized by a progressive accumulation of lipofuscin in dopamine-containing perikarya, a markedly reduced dopamine content per cell as determined visually by histofluorescence, and an increase in the number of large, fluorescent axonal dilations in dopamine-containing fibers of the mesolimbic and nigrostriatal systems. These data suggest that heterogeneous morphological aging patterns exist within dopamine-containing neurons of the midbrain and that based upon their terminal projection sites, various regions of the striatum and cortex may be differentially affected in the aged brain. In addition, these findings support the belief that age-related changes in neural structure are not generalized to an entire brain nucleus or cell type but are selective for individual cells within an affected area.
基底神经节神经递质系统的改变被认为是导致与衰老相关的运动功能和平衡破坏的原因。本研究使用儿茶酚胺荧光组织化学和儿茶酚胺合成酶酪氨酸羟化酶的免疫细胞化学技术，研究黑质纹状体（A9）和中脑边缘系统（A10）多巴胺能神经元与年龄相关的定性变化。本研究结果表明，在成熟成年（10个月）C57BL/6NNia小鼠中，中脑A9神经元而非所有A10神经元存在与年龄相关的形态学变化，且这种变化的严重程度逐渐增加，至少持续到30个月龄。这些变化的特征是含多巴胺的胞体中脂褐素逐渐积累，通过组织荧光目测确定每个细胞的多巴胺含量显著降低，以及中脑边缘系统和黑质纹状体系统含多巴胺纤维中大型荧光轴突扩张数量增加。这些数据表明，中脑含多巴胺神经元内存在异质性形态学衰老模式，并且基于其终末投射部位，纹状体和皮质的各个区域在老年脑中可能受到不同程度的影响。此外，这些发现支持这样一种观点，即与年龄相关的神经结构变化并非普遍存在于整个脑核或细胞类型中，而是对受影响区域内的单个细胞具有选择性。
