Murakami F, Katsumaru H, Saito K, Tsukahara N
Brain Res. 1982 Jun 17;242(1):41-53. doi: 10.1016/0006-8993(82)90494-2.
A quantitative electron microscopic analysis of the corticorubral projection was performed in the red nucleus (RN) of adult cats to determine morphological correlates of synaptic reorganization that occur following a lesion of the interpositus nucleus (IP). Corticorubral synaptic endings were identified by lesioning the sensorimotor cortex 2-6 days before electrophysiological experiments. Horseradish peroxidase (HRP) was injected into electrophysiologically identified RN neurons. Sagittal sections 100 micrometers thick were cut and reacted by diaminobenzidine. Sections containing HRP-positive neurons were selected and embedded in Epon. In normal cats, degenerating corticorubral terminals in the RN region frequently made contact with dendritic profiles, having small cross-sections, while a few made contact with somatic profiles. Similar results were obtained when degenerating terminals making contact with HRP-filled dendrites were analyzed. In the experimental animals, the cortical lesion was performed more than 8 weeks after lesion of the IP. In these animals, degenerating corticorubral terminals were frequently found on proximal dendrites and somata in RN region and HRP-positive neurons in contrast to the findings in normal cats. The results indicate that new corticorubral synapses were formed on proximal dendrites and somata of RN neurons as a consequence of IP lesions.
对成年猫红核（RN）进行皮质红核投射的定量电子显微镜分析，以确定在间位核（IP）损伤后发生的突触重组的形态学相关性。在电生理实验前2 - 6天，通过损伤感觉运动皮层来识别皮质红核突触末梢。将辣根过氧化物酶（HRP）注入经电生理鉴定的RN神经元。切取100微米厚的矢状切片，用二氨基联苯胺进行反应。选择含有HRP阳性神经元的切片并包埋在环氧树脂中。在正常猫中，RN区域退化的皮质红核终末经常与横截面较小的树突轮廓接触，而少数与胞体轮廓接触。分析与充满HRP的树突接触的退化终末时也得到了类似结果。在实验动物中，皮质损伤在IP损伤8周后进行。与正常猫的结果相反，在这些动物的RN区域，退化的皮质红核终末经常出现在近端树突和胞体以及HRP阳性神经元上。结果表明，IP损伤导致在RN神经元的近端树突和胞体上形成了新的皮质红核突触。
