大鼠腰髓膨大部脊髓小脑束神经元向小脑皮质的投射

Spinocercbellar projections from the Lumbar Enlargement in the CAT

将大鼠胸髓在Ｔ＿（１０）—Ｔ＿（１１）间的左侧半横切断，然后将ＷＧＡ—ＨＲＰ注入腰髓膨大部，观察标记终末（Ｌａｂｅｌｅｄｔｅｒｍｉｎａｌｓ，ＬＴ）在小脑皮质的分布。结果表明：当ＷＧＡ—ＨＲＰ注入腰髓膨大左侧时，ＬＴ主要分布在前叶（约占全部ＬＴ的７５％），其中Ⅲ和Ⅳ小叶最多（３８％和２６％），后叶较少（２５％）。ＬＴ集中分布在小叶尖端，中间部较少，基部更少。注入同侧的小脑皮质ＬＴ较多（８２％），对侧较少（１８％）。在Ⅲ和Ⅳ小叶的横切面上ＬＴ可以划分为距中线１．０～１．５ｍｍ，１．５～２．０ｍｍ，２．０～２．５ｍｍ３个集中分布区。当ＷＧＡ—ＨＲＰ注入腰髓膨大右侧时，ＬＴ主要分布在前叶（７８％），其中Ⅲ和Ⅳ小叶最多（２７％和２４％），后叶较少（２２％）。ＬＴ主要分布在小叶的中间部，小叶尖端较少，基部更少。注入部同侧小脑皮质ＬＴ较多（９０％），对侧较少（１０％）。在Ⅲ和Ⅳ小叶的横切面上它们可以区分为距中线０．５～１．０ｍｍ，１．０～１．５ｍｍ，１．５～２．０ｍｍ３个集中分布区。

he distrbution of labeled terminals from the Lumbar Enlargement to the cerebellar cortex wasstudied by anterograd of WCA-HRP to labele only noruon grops with crossed and uncrossed axons,the hemisection in the spinal cord was placed at T10-T11 on the left side.When the WGA-HRP was injected in the left side of Lumbar Enlargement,labeled terminals(LT)were seen mainly in anterior lobe,accounted for about 75%of the total.The great majorty of theLT were seen in lobule Ⅲ and Ⅳ(about 38%and 26%).About 82%and 18%of the total number ofLT were in ipsilateral and contralateral cerebelar cortex respectively.In the sagittal plane of the cere-bellum the LT were distributed mainly in superf1cial of the apicobasal extent of tbe lobule.In the hori-zontal plane of the lobules Ⅲand Ⅳ LT were distributed in three areas,they were located between1.0～1.5mm,1.5～2.0mm,2.0～2.5mm lateral to the midline respecrively.When the WGA-HRP was injected in the rightside of the Lumbar Enlargement the number o f LTwere about 78%and 22%in anterior lobe and posterior lobe.In the sagittal plane of the cerebellum theLT were distributed maiT1ly in the intermadeate region of the apicobasal extent of the lobule.In the hor-izontal plane of the lobules Ⅲ and Ⅳ LT were destributed in three areas,they were located beetween 0.5～1.0mm,1.0～1.5mm1.5～2.0mm,lateral to the midline.About 90%of the LT were distributedipsilateraI to their cells of origin,a contralateral about 10%.