Skoff R P
J Comp Neurol. 1975 Jun 15;161(4):595-611. doi: 10.1002/cne.901610408.
The ultrastructure of pulse labeled (3-H-thymidine) cells in rat optic nerve undergoing Wallerian degeneration is described. The study was limited to the first ten days after enucleation since cell proliferation during this interval is greater than in normal optic nerve (Skoff and Vaughn, '71). Approximately one-third of the pulse labeled cells are astrocytes. The majority of the proliferating astrocytes are in a reactive state, having changed their normal fibrous appearance to one showing a paucity of filaments. Thirty percent of the pulsed cells can be classified as microglia. Only immature oligodendrocytes proliferate, and they account for less than 10% of the pulse labeled cells. About 30% of the labeled population are undifferentiated glial precursor cells. Electron microscopic autoradiographic data obtained from normal optic nerve and presented in this paper indicates that glial precursor cells which have divided shortly before enucleation continue to proliferate after it. The evidence suggest that recently formed glial precursor cells transform into phagocytes following enucleation. Less than 3% of the pulse labeled cells examined in this study are ultrastructurally similar to mononuclear leukocytes. The results of the present study together with previous studies of degenerating optic nerve indicate that most phagocytes in Wallerian degeneration are derived from proliferation of intrinsic glia rather than from an invasion of exogenous cells.
本文描述了经历华勒氏变性的大鼠视神经中脉冲标记（³H - 胸腺嘧啶核苷）细胞的超微结构。该研究限于眼球摘除后的头十天，因为在此期间细胞增殖比正常视神经中更旺盛（斯科夫和沃恩，1971年）。大约三分之一的脉冲标记细胞是星形胶质细胞。大多数增殖的星形胶质细胞处于反应状态，已将其正常的纤维外观转变为细丝稀少的外观。30%的脉冲细胞可归类为小胶质细胞。只有未成熟的少突胶质细胞增殖，它们占脉冲标记细胞的比例不到10%。约30%的标记细胞群体是未分化的神经胶质前体细胞。本文呈现的从正常视神经获得的电子显微镜放射自显影数据表明，在眼球摘除前不久分裂的神经胶质前体细胞在摘除后继续增殖。证据表明，新形成的神经胶质前体细胞在眼球摘除后转变为吞噬细胞。本研究中检查的脉冲标记细胞中，超微结构与单核白细胞相似的不到3%。本研究结果与先前关于变性视神经的研究一起表明，华勒氏变性中的大多数吞噬细胞源自内在神经胶质细胞的增殖，而非外源性细胞的侵入。
