"Anoikis" of oligodendrocytes induced by Wallerian degeneration: Ultrastructural observations
"Anoikis" of oligodendrocytes induced by Wallerian degeneration: Ultrastructural observations
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DOI：
10.1089/089771504772696002
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发表时间：
2004-01-01
影响因子：
4.2
通讯作者：
Kumagai, T
中科院分区：
文献类型：
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作者：
Abe, Y;Yamamoto, T;Kumagai, T
少突胶质细胞在远离实验性脊髓损伤的白色物质束中发生凋亡，尽管其意义尚不清楚。然而，我们的超微结构研究使我们能够推测其神经生物学意义。在Th11水平横断雄性Wistar大鼠（4周龄）的脊髓。在术后第4、5和7天，对动物进行经心灌注固定。将取出的帘线包埋在环氧树脂中并通过电子显微镜检查。包埋后，末端脱氧核苷酸转移酶介导的生物素化脱氧尿苷三磷酸缺口末端标记（TUNEL）法也进行了。在横断上方的退行性背柱中，总是发现凋亡的少突胶质细胞的轮廓，嵌入由扩张的退行性髓鞘形成的空间中。通常，髓鞘中扩张的空间缺乏任何明显的背景蛋白质基质。在电镜TUNEL法中，这些凋亡细胞的电子密度与核异染色质化一致。总之，在沃勒变性过程中，我们观察到少突胶质细胞在髓鞘分裂形成的空间中凋亡。这些退化的细胞被封闭在由分裂的髓鞘形成的充满超滤液的空间中，使人联想到“失巢凋亡”。"
Oligodendrocytes undergo apoptosis in the white matter tracts remote from the experimental cord injury, although its significance is not understood. Our ultrastructural study, however, enabled us to speculate on its neurobiological implications. The spinal cords of male Wistar rats (4 week-old) were transected at Th11 level. At 4, 5, and 7 days after surgery the animals were transcardially perfusion-fixed. The removed cord was embedded in epoxy resin and examined by electron microscopy. Post-embedding terminal deoxynucleotidyl transferase-mediated biotinylated deoxyuridine triphosphate nick end labeling (TUNEL) method was also performed. In the degenerative dorsal column above the transection, profiles of apoptotic oligodendrocytes were always found, embedded in a space formed by dilated degenerative myelin lamellae. Often, the dilated space in the myelin sheath lacked any apparent background proteinaceous matrix. In the electron microscopic TUNEL method, these apoptotic cells were electron dense in accordance with nuclear heterochromatinization. In conclusion, in the process of Wallerian degeneration, we observed the apoptosis of oligodendrocytes in a space formed by the split myelin sheath. These degenerative cells, which were enclosed in an ultrafiltrate-filled space formed by split myelin lamellae, were reminiscent of "anoikis."