大鼠外侧楔核向小脑投射的追踪研究——PHA-L法

THE PROJECTIONS FROM THE EXTERNAL CUNEATE NUCLEUS TO THE CEREBELLUM OF THE RAT. IMMUNOHISTOCHEMICAL LOCALIZATION OF AXONALLY TRANSPORTED PLANT LECTIN PHA SEOLUS VULGARIS-LEUCOAGGLUTININ(PHA-L)

用菜豆白细胞凝集素(PHA-L)顺行追踪大鼠外侧楔核向小脑的投射。将PHA-L溶液电泳导入大鼠的外侧楔核后,用ABC免疫组织化学法可以清楚地显示出被标记神经细胞、纤维及终末的形态。结果表明,大鼠外侧楔核的投射纤维经同侧绳状体进入小脑。终末区主要包括小脑前、后叶的双侧蚓部、同侧前叶的半球部、同侧Ⅷ小叶的旁蚓部、Ⅸa小叶及同侧旁正中小叶的内侧部。Ⅳ-Ⅴ小叶上终末密度最高,并形成三条平行于正中矢状平面的终末带。在同侧脚Ⅰ及Ⅸb小叶上发现少量终末。结果还提示,外侧楔核无纤维终末至小脑中央核。

Projection system from the external cuneate nucleus to the cerebellum was studied in the rat by anterogradely transported Phaseolus vulgaris-leucoagglutinin(PHA-L). The morphology of the labeled neurons, mossy fibers, and rosette terminals was well revealed by ABC immunohistochemical method after the PHA-L had been delivered iontophoretically into the external cuneate nucleus of the rat. The result indicates that the fibers project from the external cuneate nucleus to the cerebellum via ipsilateral restiform body, and that mossy fibers terminate mainly in the inner part of the cerebellar granular layer. The fibers areas comprise the anterior and posterior vermis bilaterally and the ipsilateral hemispheral parts of the anterior lobe and the paravermis of lobule Ⅷ, ipsilateral Ⅸa as well as the medial part of the ipsilateral paramedian lobule, Of which the most intensive appears in Ⅳ-Ⅴ lobules showing three terminal bands parallel to the sagittal line of the cerebellum. A few projections to the ipsilateral Crus Ⅰ and Ⅸb were found. The result also suggests that the external cuneate nucleus has no fiber terminals in the central cerebellar nuclei.