Sakai S T
Department of Anatomy, College of Human Medicine, Michigan State University, East Lansing 48824.
Exp Brain Res. 1990;79(2):240-8. doi: 10.1007/BF00608232.
The corticospinal projections from areas 4 and 6 were investigated in the raccoon using the horseradish peroxidase (HRP) retrograde tracing technique. Multiple injections of lectin bound HRP and HRP were made into either the cervical or lumbar cord in 7 anesthetized raccoons. Retrogradely labeled neurons were observed throughout a wide extent of areas 4 and 6a beta. The HRP positive cells were most numerous within the dorsal bank of the cruciate sulcus within area 4 and continued around the fundus to occupy the lateral two-thirds of the ventral bank of the cruciate sulcus within area 6a beta. No labeled cells were observed in the more medially located area 6a alpha. Although the HRP positive cells observed following the lumbar cord injections were situated slightly more medial and caudal to those observed following the cervical cord injections, considerable overlap between the two projections was noted. The corticospinal projections arising from areas 4 and 6a beta in the raccoon largely correspond in location to the regions functionally defined as the primary motor cortex and the supplementary motor area, respectively.
利用辣根过氧化物酶（HRP）逆行追踪技术，对浣熊中来自4区和6区的皮质脊髓投射进行了研究。在7只麻醉的浣熊中，将凝集素结合的HRP和HRP多次注射到颈髓或腰髓中。在4区和6aβ区的广泛区域观察到了逆行标记的神经元。HRP阳性细胞在4区内十字沟的背侧缘最为密集，并围绕沟底延伸，占据6aβ区内十字沟腹侧缘的外侧三分之二。在更内侧的6aα区未观察到标记细胞。尽管在腰髓注射后观察到的HRP阳性细胞比颈髓注射后观察到的细胞位置稍偏内侧和尾侧，但注意到这两种投射之间有相当大的重叠。浣熊中来自4区和6aβ区的皮质脊髓投射在位置上大体分别对应于功能上定义为初级运动皮层和辅助运动区的区域。
