Katsumaru H, Murakami F, Wu J Y, Tsukahara N
Neurosci Res. 1984 Feb;1(1):35-44. doi: 10.1016/0168-0102(84)90028-2.
The presence of glutamic acid decarboxylase (GAD), the enzyme synthesizing gamma-aminobutyric acid (GABA), was investigated in the red nucleus by an immunocytochemical method. The ipsilateral sensorimotor cortex was ablated prior to the immunocytochemical procedures to examine whether cortical neurons make synaptic contacts with GAD-immunoreactive neurons. Small GAD-immunoreactive neurons with a major diameter of 16.1 +/- 3.2 micron (mean +/- S.D.) were observed in the red nucleus under both light and electron microscopy. They were uniformly distributed throughout the nucleus. Degenerating axon terminals were found making synaptic contact with GAD-immunoreactive neurons in the red nucleus, which suggests that there is an input from the ipsilateral sensorimotor cortex to these neurons. This observation, along with our previous findings that GABAergic axon terminals make synaptic contact with the rubrospinal neurons, provides anatomical evidence for the presence of intrinsic GABAergic interneurons which mediate cortical inhibition in cat rubrospinal neurons.
采用免疫细胞化学方法研究了红核中谷氨酸脱羧酶（GAD，合成γ-氨基丁酸（GABA）的酶）的存在情况。在进行免疫细胞化学操作之前，先切除同侧感觉运动皮层，以检查皮层神经元是否与GAD免疫反应性神经元形成突触联系。在光学显微镜和电子显微镜下，均在红核中观察到了主要直径为16.1±3.2微米（平均值±标准差）的小GAD免疫反应性神经元。它们均匀地分布于整个红核。发现退化的轴突终末与红核中的GAD免疫反应性神经元形成突触联系，这表明存在从同侧感觉运动皮层到这些神经元的输入。这一观察结果，连同我们之前发现的GABA能轴突终末与红核脊髓神经元形成突触联系，为存在介导猫红核脊髓神经元皮层抑制的内在GABA能中间神经元提供了解剖学证据。
