不同损伤模型背根节内p75NTR的表达及其意义

目的：探讨不同损伤模型中背根神经节（dorsal root ganglion，DRG）神经元和胶质细胞中p75NTR免疫产物的变化及其意义。方法：建立单纯坐骨神经损伤、单纯脊髓背索损伤以及合并损伤（脊髓背索损伤前1周损伤坐骨神经）模型，动物被随机分成正常组、单纯坐骨神经损伤组、单纯脊髓损伤组、合并损伤组。从脊髓损伤处嘴侧5mm处注入快蓝（fastblue，FB）以逆行标记DRG中感觉神经元，用免疫荧光组织化学方法观察不同模型中p75NTR在背根节神经元和胶质细胞的阳性产物，并结合FB逆行示踪观察FB阳性神经元中p75NTR的表达。结果：单纯坐骨神经损伤组背根节中胶质细胞源性p75NTR免疫阳性产物较正常组增加，神经元中p75NTR阳性产物较正常组低；单纯脊髓损伤组胶质细胞源性p75NTR免疫阳性产物较单纯坐骨神经损伤组和合并损伤组明显降低；坐骨神经损伤合并脊髓损伤组p75NTR的表达与单纯坐骨神经损伤组相似，在胶质细胞内上调，在神经元内降低，大多数FB标记的感觉神经元p75NTR表达呈阴性，但被p75NTR免疫阳性胶质细胞围绕。结论：不同损伤模型DRG中，p75NTR阳性产物在神经元和胶质细胞中具有明显差异，胶质细胞源性p75NTR可能参与了脊髓损伤后上行传导束的再生。

Expression and significance of p75NTR in dorsal root ganglia in different injury models

Objective To determine the expression and significance of p75NTR in the neuron and glia of dorsal root ganglia(DRG) in different injury models.MethodsThe models of sciatic nerve injury,spinal cord injury,and combined injury(sciatic nerve injury one week prior to spinal cord injury) were established.The rats were randomly divided into a normal group,a sciatic nerve injury group,a spinal cord injury group,and a combined injury group.The sensory neurons in the DRG were labeled by fast blue(FB) injected in the ...