论文部分内容阅读
将６只Ｗｉｓｔｅｒ大鼠脊髓Ｌ（１～３）段双侧后根切断，并将ＨＲＰ注入小脑内。术后分别在２、３、４天灌杀，取出Ｌ（１～３）脊髓节段，对ＨＲＰ标记的脊髓边缘细胞及其与溃变末梢的突触联系进行了电镜观察。结果表明，在脊髓边缘细胞的胞体或近侧树突表面发现有少量的溃变终末。根据溃变终末内小泡的形状，它们属于Ｓ型和Ｆ型即球形和扁平形小泡。根据溃变终末的外形又可分为圆型和细长型。按不同术后存活期，这些终末显示的溃变特点有所不同。术后２天溃变终末主要呈电子密度增高象；术后３天溃变终末中的线粒体肿胀、溶解以及部分突触小泡溶解；术后４天的溃变终末内则表现突触小泡和线粒体大部溶解消失。各类溃变末梢周围均可见到有胶质细胞突起包绕或充填。本研究进一步证明，作为脊小脑前束起始细胞的脊髓边缘细胞所接受的外周传入从性质和特点上均与脊小脑后束的起始细胞有所不同。这些结构的不同说明脊髓边缘细胞在向小脑输送信息中有其特殊功能。
The bilateral posterior roots of L (1-3) spinal cord of 6 Wister rats were cut off, and HRP was injected into the cerebellum. The rabbits were sacrificed at 2, 3, 4 days after operation, and the spinal cord segments of L (1-3) were removed. The synaptic connections between HRP-labeled spinal marginal cells and the degenerative terminals were observed under electron microscope. The results showed that a small amount of terminal degranulation was found on the surface of the cell body or proximal dendrites of the marginal cells of the spinal cord. Depending on the shape of the vesicle end-vesicles, they belong to S-type and F-type, ie, spherical and flat-shaped vesicles. According to the final shape of the ulcer can be divided into round and slender. According to different postoperative survival, these terminals showed different characteristics of the degeneration. At the end of the second day after operation, the main signs of electron density increase were as follows: the mitochondria were swollen, dissolved and some of the synaptic vesicles were dissolved in the terminal three days after operation; Bullactomy and mitochondria dissolved most disappear. Around the various types of degeneration can be seen around the glial protrusions or filling. This study further demonstrates that the peripheral afferent receptiveities of the marginal cells of the spinal cord that serve as starting cerebrospinal precursors are different in character and nature from that of the starting cerebellum. The differences in these structures suggest that the marginal cells of the spinal cord have their special function in delivering information to the cerebellum.