Schwartz A M, Parakkal M, Gulley R L
Am J Anat. 1983 May;167(1):33-41. doi: 10.1002/aja.1001670104.
The postnatal development of the spiral ganglion in the albino rat was studied using light and electron microscopy. The morphological characteristics distinguishing type 1 from type 2 spiral ganglion cells were defined, and the critical period for distinguishing the two types of neurons was identified. At birth, the spiral ganglion consists of a homogeneous population of small, densely packed, spherical cells that have large cytoplasmic-to-nuclear ratios. During the first postnatal week, the cells mature slowly. At this period the myelin sheath around the cell bodies generally consists of only a few layers of loose myelin. Long glial fingers extend around the cell processes and soma, particularly the filopodial extensions of the somatic membrane. Type 2 spiral ganglion cells can be distinguished at postnatal day 8. Viewed with the phase-contrast microscope these cells are smaller and have more darkly staining nuclei and more lightly staining cytoplasm than the type 1 cells. The most characteristic ultrastructural features of the type 2 neurons are the densely packed neurofilaments in the cytoplasm and lack of compact myelin around the cell soma. By day 14, spiral ganglion cells are morphologically mature, although the myelin sheath continues to thicken. The results are discussed in relation to the electrophysiological development of the auditory system and the morphological maturation of the organ of Corti.
利用光学显微镜和电子显微镜研究了白化大鼠螺旋神经节的出生后发育情况。定义了区分1型和2型螺旋神经节细胞的形态学特征，并确定了区分这两种神经元的关键时期。出生时，螺旋神经节由一群均匀的小细胞组成，这些细胞紧密排列成球形，细胞质与细胞核的比例很大。在出生后的第一周，细胞成熟缓慢。在此期间，细胞体周围的髓鞘通常仅由几层松散的髓磷脂组成。长的神经胶质指状物围绕细胞突起和胞体延伸，特别是胞体膜的丝状延伸部分。2型螺旋神经节细胞在出生后第8天可以被区分出来。用相差显微镜观察，这些细胞比1型细胞更小，细胞核染色更深，细胞质染色更浅。2型神经元最具特征性的超微结构特征是细胞质中密集排列的神经丝以及细胞体周围缺乏紧密的髓磷脂。到第14天，螺旋神经节细胞在形态上已经成熟，尽管髓鞘会继续增厚。结合听觉系统的电生理发育和柯蒂氏器的形态成熟对结果进行了讨论。
