期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1993
卷号:90
期号:14
页码:6820-6824
DOI:10.1073/pnas.90.14.6820
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Cerebral hemispheres from mouse embryos at 15 days of gestation were dissociated and maintained in culture for several weeks in a medium which permitted homochronic and homotypic oligodendrocytes and neurons to interact in the presence of other central nervous system cells. After 13-14 days in culture a few oligodendrocytes changed from highly branched, "sun-like," nonmyelinating cells to sparcely branched myelinating cells. The number of fibers myelinated per oligodendrocyte ranged from 1 to 10, similar to that described previously in vivo in the corpus callosum. When an oligodendrocyte began to myelinate, it immediately myelinated a maximum number of fibers, suggesting that the number of axons to be myelinated by the oligodendrocyte was predetermined. When only one fiber was in the vicinity of a myelinating oligodendrocyte, whorls of myelin-like figures were seen at the tip of oligodendrocyte processes that had not reached an axon. Myelinated fibers were unambiguously identified as axons both by immunostaining and by electron microscopy. Myelin was not observed around astrocyte processes or around dendrites. The exclusive myelination of axons suggests the existence of a specific axonal recognition signal which attracts oligodendrocyte processes.