Sten Shi Tie-Jun, Holmberg Kristina, Xu Zhi-Qing David, Steinbusch Harry, de Vente Jan, Hökfelt Tomas
Department of Neuroscience, Karolinska Institute, S-171 77 Stockholm, Sweden Department of Psychiatry and Neuropsychology, University of Maastricht, Maastricht, The Netherlands.
Pain. 1998 Dec;78(3):171-180. doi: 10.1016/S0304-3959(98)00124-9.
Using the indirect immunofluorescence method, the distribution of cyclic GMP (cGMP) and nitric oxide synthase (NOS) was investigated in lumbar 5 dorsal root ganglia (DRGs) of untreated rats 1, 3 and 7 days following sciatic nerve section (axotomy). Untreated and axotomized (7 days) rats were also studied after perfusion with the NO donor sodium nitroprusside (SNP). Moreover, rats were injected with carrageenan lambda into the unilateral hindpaw and studied after 6 h, 1 day or 2 days. An increase in the number of cGMP-positive satellite cell profiles was found in axotomized DRGs at 3 days with lower numbers after 7 days. In contrast, no change in cGMP-like immunoreactivity (LI) in satellite cell profiles was detected 1 day after axotomy or 6h, 1 day or 2 days after inflammation, as compared to controls. Axotomy induced a marked increase in the percentage of NOS-immunoreactive (IR) neuron profiles in the ipsilateral DRGs as follows: 3.0% at 1 day, 15% at 3 days and 25% at 7 days, whereas no significant change was found in the expression of NOS-LI in the inflamed DRGs as compared to untreated DRGs. Between 15 and 20% of all NOS-positive neuron profiles were surrounded by, or in partial contact with, cGMP-IR satellite cells in controls 1 and 3 days after axotomy, whereas the corresponding figure was around 5% after 7 days. After SNP perfusion 60-70% of all DRG neuron profiles were partly or totally associated with cGMP-positive satellite cell profiles, with no significant difference between untreated and axotomized ganglia. The nerve injury-induced, parallel upregulation of NOS in DRG neurons and cGMP in satellite cells in the initial phase after axotomy suggests an involvement of NO as a signalling molecule between neurons and satellite cells in DRGs, especially after peripheral nerve injury, perhaps exerting a survival effect as recently proposed by Thippeswamy and Morris (1997).
采用间接免疫荧光法，研究坐骨神经切断（轴突切断）后1天、3天和7天未处理大鼠腰5背根神经节（DRG）中环磷酸鸟苷（cGMP）和一氧化氮合酶（NOS）的分布。未处理和轴突切断（7天）的大鼠在灌注一氧化氮供体硝普钠（SNP）后也进行了研究。此外，将角叉菜胶λ注射到大鼠单侧后爪，分别在6小时、1天或2天后进行研究。发现轴突切断的DRG中，cGMP阳性卫星细胞轮廓数量在3天时增加，7天时数量减少。相比之下，与对照组相比，轴突切断1天后或炎症后6小时、1天或2天，卫星细胞轮廓中的cGMP样免疫反应性（LI）没有变化。轴突切断导致同侧DRG中NOS免疫反应性（IR）神经元轮廓的百分比显著增加，如下所示：1天时为3.0%，3天时为15%，7天时为25%，而与未处理的DRG相比，炎症DRG中NOS-LI的表达没有显著变化。在轴突切断后1天和3天的对照组中，所有NOS阳性神经元轮廓中有15%至20%被cGMP-IR卫星细胞包围或部分接触，而7天后相应数字约为5%。SNP灌注后，所有DRG神经元轮廓中有60%至70%部分或完全与cGMP阳性卫星细胞轮廓相关，未处理和轴突切断的神经节之间没有显著差异。轴突切断后初始阶段，DRG神经元中NOS和卫星细胞中cGMP的平行上调表明，NO作为DRG中神经元和卫星细胞之间的信号分子参与其中，尤其是在周围神经损伤后，可能如Thippeswamy和Morris（1997）最近所提出的那样发挥存活作用。
