Yick L W, Wu W, So K F, Yip H K
Faculty of Medicine, The University of Hong Kong, Hong Kong.
Exp Neurol. 1999 Sep;159(1):131-8. doi: 10.1006/exnr.1999.7134.
The present study examined the effects of peripheral nerve (PN) graft and neurotrophic factors on the expression of nitric oxide synthase (NOS) and the survival of Clarke's nucleus (CN) neurons at the first lumbar spinal segment (L1) 15 days after hemisection of the spinal cord at T11. Normal intact CN neurons did not express NOS. Forty-one percent of the ipsilateral CN neurons survived after hemisection at T11, and 48% of the surviving neurons expressed NOS. Transplantation of PN graft at the lesion site promoted the survival of CN neurons to 71% and increased the expression of NOS to 70%. Continuous infusion of brain-derived neurotrophic factor, ciliary neurotrophic factor, and neurotrophic-3, but not glial cell-derived neurotrophic factor, at the lesion site enhanced the survival of CN neurons to about 65%. Among the surviving neurons about 70% were NOS-positive. These results indicated that transplantation of autologous PN graft or continuous infusion of neurotrophic factors could enhance the survival of axotomized CN neurons. In addition, the survival-promoting function of the neurotrophic agents was coincided with the upregulation of the expression of NOS. However, whether the upregulation of NOS expression in injured CN neurons is related to the rescue function or is a side effect of the neurotrophic factors is not clear and needed further investigation.
本研究检测了在T11脊髓半横断术后15天，周围神经（PN）移植和神经营养因子对第一腰脊髓节段（L1）克拉克核（CN）神经元一氧化氮合酶（NOS）表达及存活情况的影响。正常完整的CN神经元不表达NOS。T11半横断术后，同侧CN神经元有41%存活，且48%的存活神经元表达NOS。在损伤部位移植PN移植物可使CN神经元的存活率提高到71%，并使NOS的表达增加到70%。在损伤部位持续输注脑源性神经营养因子、睫状神经营养因子和神经营养因子-3，但不包括胶质细胞源性神经营养因子，可使CN神经元的存活率提高到约65%。在存活的神经元中，约70%为NOS阳性。这些结果表明，自体PN移植物移植或持续输注神经营养因子可提高轴突切断的CN神经元的存活率。此外，神经营养剂的促存活功能与NOS表达的上调相一致。然而，损伤的CN神经元中NOS表达的上调是与挽救功能相关还是神经营养因子的副作用尚不清楚，需要进一步研究。
