猫脊髓SP可塑性终末在腰骶背根全切后板层Ⅱ的变化

Changes of SP terminals in lamian Ⅱ of cat spinal cord following dorsal rhizotomy

目的：探讨猫单侧腰骶背根全切后SP可塑性终末的改变。方法：成年雄性猫，分为急性组和慢性组，动物深麻，经灌注固定后取脊髓腰6节段做SP光镜和电镜免疫组织化学分析。结果：SP在对照侧主要分布于背角Ⅱ板层，急性组与慢性组手术侧背角SP免疫反应均明显弱于对照侧，其中以Ⅱ板层最为突出；慢性组手术侧SP免疫反应强度下降的幅度小于急性组。结论：电镜下观察到的SP终末就是光镜下SP在慢性组回升的结构基础。

Objective： To investigate the changes of SP terminals in lamina Ⅱ of cat spinal cord following dorsal rhizotomy. Methods： 10 male adult cats were divided into 2 groups： acute group, which survived 7-24 days; chronic group, which survived 2 months. After anesthesia, all cats were perfused, and the L6 segment of the spinal cord was removed and prepared for light and electron microscopy of substance P immunohistochemistry. Results： The substance P immunoreactivity was shown in laminae Ⅱ of dorsal horn in control side, which was more intensive than that of operation side in both acute and chronic groups. In the chronic group, the intensity of SP immunoreactivity of operation side decreased slightly compared to that of the acute group. Conclusion： An increase in substance P immunoreactivity shown at the light microscope level relate to the increased number of SP-containing terminals in laminae Ⅱ under the electronic microscope.