Ralston D D, Milroy A M, Holstege G
Department of Anatomy, University of California, San Francisco 94143.
Neurosci Lett. 1988 Dec 19;95(1-3):102-6. doi: 10.1016/0304-3940(88)90640-4.
The magnocellularis division of the red nucleus of the Macaca mulatta, a midbrain structure involved in processing motor information, is known by light microscopic analysis to project, via the rubrospinal tract, to the contralateral intermediate horn of the spinal cord. Physiological studies, however, provide additional evidence for direct monosynaptic connections to motoneurons subserving distal musculature. This electron microscopic study demonstrates, by analyzing the anterograde transport of 5% wheatgerm agglutinin-horseradish peroxidase injected into the red nucleus, the presence of labeled terminals synapsing upon somata and proximal dendrites of motoneurons in the lateral portion of the ventral horn of the cervical enlargement of the spinal cord. We conclude that this anatomical evidence confirms the presence of direct monosynaptic connections to spinal motoneurons in the primate.
猕猴红核的大细胞部是中脑结构，参与运动信息处理，通过光学显微镜分析可知，它经红核脊髓束投射至脊髓对侧中间带。然而，生理学研究为其与支配远端肌肉组织的运动神经元存在直接单突触连接提供了额外证据。本电子显微镜研究通过分析注入红核的5% 麦胚凝集素 - 辣根过氧化物酶的顺行运输，证明在脊髓颈膨大腹角外侧部运动神经元的胞体和近端树突上存在标记终末形成的突触。我们得出结论，这一解剖学证据证实了灵长类动物中存在与脊髓运动神经元的直接单突触连接。
