摘要
为探讨神经生长因子（NGF）在部分去背根传入猫脊髓Ⅱ板层可塑性中的作用，本文采用成年雄猫15只，建立单侧备用根模型（即切断一侧L1～5、L7～S2节段脊髓背根，保留L6背根），术后分别存活3、5和11d，灌流固定，取L5、L6、L7脊髓冻切．用2.5sNGF抗体进行ABC法免疫组化反应．每例在7张切片上测两侧Ⅱ板层内、中、外三个固定大小对应区域的灰度值。结果：三个时间组手术例L6平面Ⅱ板层NGF的平均灰度均显著地小于非手术例（P＜0．05）；而手术侧L5、L7平面Ⅱ板层NGF的平均灰度3d时均大于非手术侧（P＜0．05），5d时无显著差异（P＞0．05），11d时小于非手术侧（P＜0．05），即手术侧L5、L7Ⅱ板层灰度值随时间推移而显著减小。结果表明，手术侧L6Ⅱ板层NGF含量在三个时间组均有增加；而L5、L7Ⅱ板层NGF含量在3d时下降，5d恢复，11d增多．这种内源性NGF含量的变化可能与部分去背根脊髓Ⅱ板层的可塑性变化有关．
For exploration of the effect of nerve growth factor (NGF) in plasticity of spinal lamina Ⅱ, fifteen adult male catswere used to establish spared dorsal root prcparation (i. e. rhizotomy of uniIateral L1～5, L7 ～S2 hind limb dorsal roots,Leaving L6 as a spared dorsal root). The animals were allowed to survive 3 days, 5 days and 11 days respectively (eachgroup containing five cats). The cats were perfused and fixed with 4% para formaldehyde. The L5, L6, L7 segments ofspinal cord were sectioned and 30 pm thickness frozen sections were cut transversely. The sections were immunostained with2. 5s NGF antibody(Sigma) by free floating technique, The ABC kit was used and the sections were stained with brown col-or method. The gray degree of sections in spinal lamina Ⅱ was determined with image analysis system. The average of graydegree was treated by statistical meThod. The NGF immunoreactivity (NGF-IR) presented mainly in spinal laminae Ⅰ andⅡ of both sides. The distribution of NGF-IR corresponded well with that of NGF receptor of primary affetent nerve fibers(as C and Aδ afferents) and their terminals in spinal cord. It suggested that NGF is involved in maintenance of the normalactivity of dorsal root terminals (as c and Aa fibers) in laminae Ⅰ and Ⅱ -the targets of their DRG neurons. Quantitativeanalysis resulted as following: (1) the average of gray degree in operated side laminal Ⅱ of L5, L7 segments was significant-ly bigher than that of unoperated side on the 3rd day after partiat deafferentation (P<0. 05), indicating that the content ofNGF was decreased which might be caused by deafferentation. The gtay degree of Lamina Ⅱ of L5, L7 segments on bothsides was not statistically different (P>0. 05) on the 5th day, indicating that the content of NGF within operated side lami-na, of L5, L7 segments was recovered to normal level on 5th day after partial deafferentation. The gray degree on operatedside lamina Ⅱ of L5, L7 segments was significantly lower than that of unoperated side (P<0. 05) on the 11th day, indicatingthat the content of NGF was increased. (2) The gray degtee of operated side L6 lamina Ⅱ was lower than that of unoperatedside on the 3th, 5th and 11th days following operation, indicating that the content of NGF was increased after operation. Itsuggested that the increase in amount of NGF in spinal lamina Ⅱ of spared root level (L6) and later on their cranial(L5) andcaudal(L7) levels might be reIated with the plasticity of partial dorsal rhizotomized dorsal horn.
出处
《神经解剖学杂志》
CAS
CSCD
北大核心
1997年第4期362-366,共5页
Chinese Journal of Neuroanatomy
基金
国家自然科学基金
关键词
脊髓Ⅱ板层
神经生长因子
免疫组织化学
plasticity, spinal lamina Ⅱ, immunohistochemistry, nerve growth factor, spared dorsal root preparation, im-age analysis
