大鼠前庭核向脊髓节段投射的研究

将霍乱毒素亚单位B(CTB)分别注入大鼠单侧或双侧不同脊髓节段以观察前庭核向脊髓的节段投射。结果 :①上颈髓注入例的标记细胞主要见于前庭外侧核的尾端腹侧部、前庭降核的尾侧部和前庭内侧核的小细胞部 ;②颈膨大注入例的标记细胞仅见于前庭外侧核的尾端腹侧部及弥散分布于前庭降核、前庭内侧核 ;③胸髓及腰髓注入例的标记细胞广泛分布于前庭外侧核和前庭降核 ,其中以前庭外侧核的头端背侧部最为密集 ,并仅稀疏地分布于前庭内侧核的小细胞部 ;④骶髓注入例的标记细胞仅弥散地分布于前庭外侧核和前庭降核。提示 :起源于前庭降核和前庭外侧核的纤维可一直投射到骶髓节段 ,而起源于前庭内侧核的纤维仅投射到上腰髓节段

Projection to the Spinal Cord from the Vestibular Nuclei in the Rattraced by CTB Method

Projection from the vestibular nuclei to the spinal cord was examined following injection of cholera toxin subunit B at various levels of the spinal cord in the rat. The results were as follows: ① The majority of the labeled cells were seen in the caudal ventral of LVN, caudal of DVN and MVmc of MVN from the injections into the upper cervical segment. ② The labeled cells were only seen in the caudal ventral of LVN, and distributed diffusely in the DVN and MVN from the injections into the cervical enlargement segment. ③ The labeled cells were distributed in all parts of LVN and DVN, especially densest in the rostral dorsal of LVN, and seldom seen in the MVmc of MVN from the injections into the thoracic and lumbar segment. ④ The labeled cells from the injections into the sacral segment distributed sparsely in the LVN and DVN. The result indicates that the fibers of origin from the DVN and LVN projected directly to the sacral segment, while the fibers of origin from the MVN only projected to the upper lumbar segment.