手术破坏八只大鼠皮质,同时注HRP于脊髓颈部,用溃变HRP电镜技术观察了巨细胞网状核(NRG)中皮质投射纤维的突触结构和投向脊髓的HRP标记神经元及二者的相互关系。结果表明:皮质向NRG投射纤维的突触基本为轴—树型、非对称型突触,突触小泡以圆形无颗粒小泡为主,偶见较大的圆形颗粒小泡。部分溃度突触与HRP标记的树突形成突触,据此认为,大脑皮质下行投射系统中,存在着一种间接的皮质脊髓束:皮质—NRG—脊髓通路。 Eight cortical rats were perfused and HRP was injected into the neck of the spinal cord at the same time. The synaptic structure of cortical projection fibers and the HRP-labeled neurons in the spinal cord were observed by degenerative HRP electron microscopy. The relationship between the people. The results showed that the synapses of cortical fibers projected to NRG were basically axial-tree type and asymmetric synapses. The synaptic vesicles mainly consisted of round, non-granular vesicles, with occasional larger round-shaped vesicles. Partially collapsing synapses form a synapse with HRP-labeled dendrites, suggesting that there is an indirect corticospinal tract in the cortical descending projection system: the cortical-NRG-spinal pathway.