Neale E A, Bowers L M, Smith T G
Laboratory of Developmental Neurobiology, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892.
J Neurosci Res. 1993 Jan;34(1):54-66. doi: 10.1002/jnr.490340107.
Neurons in dissociated cell culture provide a favorable system for the quantitative analysis of structural changes and the examination of structure-function relationships during development. Fragment C of tetanus toxin was used to label neurons in murine spinal cord cell cultures and dendrite outgrowth was monitored by a number of measures. The dissociated neurons increased in morphologic complexity from approximate spheres to highly branched structures during the first week in culture. Much of the structural complexity of the dendrite arbor, as quantified by fractal dimension, was established within 48 hr after plating, i.e., prior to the development of interneuronal contacts. During the first few days in culture, dendrite branching complexity increased more rapidly than dendrite size, whereas after 4 days, fractal dimension remained relatively constant while dendrites continued to grow. Fractal analysis has provided data which suggest that the early development of dendrite branching complexity is determined intrinsically. Fractal dimension, as an effective index of morphologic complexity, should be a useful tool for the further study of extrinsic signals which might modify the generation or stabilization of dendrite form.
解离细胞培养中的神经元为发育过程中结构变化的定量分析以及结构 - 功能关系的研究提供了一个良好的系统。破伤风毒素C片段用于标记小鼠脊髓细胞培养物中的神经元，并通过多种方法监测树突的生长。在培养的第一周，解离的神经元从近似球形增加到高度分支的结构，形态复杂性增加。通过分形维数量化的树突分支结构的大部分复杂性在接种后48小时内建立，即在神经元间接触形成之前。在培养的最初几天，树突分支复杂性的增加比树突大小的增加更快，而在4天后，分形维数保持相对恒定，而树突继续生长。分形分析提供的数据表明，树突分支复杂性的早期发育是由内在因素决定的。分形维数作为形态复杂性的有效指标，应该是进一步研究可能改变树突形态产生或稳定的外在信号的有用工具。
