Fukuda J
Dev Neurosci. 1985;7(5-6):374-94. doi: 10.1159/000112304.
In order to differentiate age-associated changes in morphological and physiological properties of mammalian nerve cells, dorsal root ganglion (DRG) cells of aged mice (C57BL/6; 98-99 weeks old) were grown in a monolayer culture. Neurite outgrowth, changes in shape and size of their soma and functional properties of their plasma membranes were compared to those of tissue-cultured DRG cells from young adult mice (4-8 weeks old). Trigeminal root ganglion (TRG) cells of aged mice were also grown in a monolayer culture, and their in vitro growth was compared to that of the aged DRG cells. Nerve cells were dissociated from DRG (or TRG) by digestion with collagenase and by trituration and were grown on collagen-coated plastic dishes for more than 14 days. Growth of neurites and changes in the size and shape of the nerve cell soma were viewed under a phase-contrast microscope, and physiological properties of the plasma membrane were studied by conventional intracellular recordings with a glass microelectrode. Both adult and aged DRG cells grew neurites of various length and underwent changes in shape and size of their soma, which could be divided into 2 stages; early and late. In the early stage of tissue culture (0-60 h in vitro), nerve cells altered their shape from a spherical to a spindle-like form. This change was not associated with the reduction in cell size. In the late stage of the tissue culture (3-14 days and thereafter), the DRG reduced their cell size, while changes in shape remained small. Quantitative comparison of the adult and aged DRG nerve cells revealed the following 3 major differences between 2 cultures: the survival fraction of the aged DRG cells counted at 36-48 h in vitro was 1/4 to 1/10 of that of the adult DRG cells in 3 different tissue culture trials; reduction in the cell size occurred much earlier in the aged than in the adult nerve cells; the rate of reduction in size of the aged DRG cells was large in comparison with that of the adult DRG cells. No difference in neurite growth or in physiological properties (resting membrane potential, input resistance, input capacitance or capability of generating both Na and Ca spikes) was detected between the aged and adult nerve cells in tissue culture.
为了区分哺乳动物神经细胞形态和生理特性的年龄相关变化，将老年小鼠（C57BL/6；98 - 99周龄）的背根神经节（DRG）细胞进行单层培养。将其神经突生长、胞体形状和大小的变化以及质膜的功能特性与年轻成年小鼠（4 - 8周龄）组织培养的DRG细胞进行比较。老年小鼠的三叉神经根神经节（TRG）细胞也进行单层培养，并将其体外生长情况与老年DRG细胞进行比较。通过胶原酶消化和研磨从DRG（或TRG）中分离神经细胞，并在胶原包被的塑料培养皿上培养超过14天。在相差显微镜下观察神经突的生长以及神经细胞胞体大小和形状的变化，并用玻璃微电极通过传统的细胞内记录研究质膜的生理特性。成年和老年DRG细胞均长出了不同长度的神经突，且胞体的形状和大小发生了变化，可分为早期和晚期两个阶段。在组织培养的早期阶段（体外0 - 60小时），神经细胞的形状从球形变为纺锤形。这种变化与细胞大小的减小无关。在组织培养的后期阶段（3 - 14天及之后），DRG细胞大小减小，而形状变化较小。成年和老年DRG神经细胞的定量比较揭示了两种培养物之间的以下3个主要差异：在3次不同的组织培养试验中，体外36 - 48小时计数的老年DRG细胞的存活分数是成年DRG细胞的1/4至1/10；老年神经细胞的细胞大小减小比成年神经细胞早得多；与成年DRG细胞相比，老年DRG细胞大小减小的速率较大。在组织培养中，老年和成年神经细胞在神经突生长或生理特性（静息膜电位、输入电阻、输入电容或产生Na和Ca峰的能力）方面未检测到差异。
