Castaño A, Bell M D, Perry V H
University Department of Pharmacology, Oxford, UK.
Neurobiol Aging. 1996 Sep-Oct;17(5):745-51. doi: 10.1016/0197-4580(96)00105-4.
Wallerian degeneration in the PNS is accompanied by the rapid recruitment of monocytes, but monocytes do not invade CNS fibre tracts undergoing Wallerian degeneration. In recent years it has become apparent that the acute inflammatory response to cell degeneration in the CNS is unlike that in other tissues. We have been interested to learn why Wallerian degeneration does not provoke a typical inflammatory response. We investigated whether the vascular endothelial cells express adhesion molecules during Wallerian degeneration in PNS and CNS. We found that in the degenerating sciatic nerve there was upregulation of ICAM-1 and VCAM-1 expression on endothelial cells in the distal stump of the injured nerve as well as at the site of the lesion. However, in the degenerating optic nerve, the endothelium failed to upregulated these molecules in the distal stump of the nerve and ICAM-1 expression was only increased in the crush site. The lack of adhesion molecule expression on CNS endothelium molecules may be an explanation for the poor leukocyte recruitment during Wallerian degeneration in CNS when compared with PNS.
外周神经系统中的沃勒变性伴随着单核细胞的快速募集，但单核细胞不会侵入正在发生沃勒变性的中枢神经系统纤维束。近年来，很明显中枢神经系统对细胞变性的急性炎症反应与其他组织不同。我们一直想了解为什么沃勒变性不会引发典型的炎症反应。我们研究了在周围神经系统和中枢神经系统的沃勒变性过程中血管内皮细胞是否表达黏附分子。我们发现，在变性的坐骨神经中，损伤神经远端残端以及损伤部位的内皮细胞上ICAM-1和VCAM-1的表达上调。然而，在变性的视神经中，神经远端残端的内皮细胞未能上调这些分子，且ICAM-1的表达仅在挤压部位增加。与外周神经系统相比，中枢神经系统内皮细胞分子上缺乏黏附分子表达可能是中枢神经系统沃勒变性过程中白细胞募集较少的一个原因。
