REGION-SPECIFIC EXPRESSION OF SUBUNITS OF IONOTROPIC GLUTAMATE RECEPTORS (AMPA-TYPE, KA-TYPE AND NMDA RECEPTORS) IN THE RAT SPINAL-CORD WITH SPECIAL REFERENCE TO NOCICEPTION
REGION-SPECIFIC EXPRESSION OF SUBUNITS OF IONOTROPIC GLUTAMATE RECEPTORS (AMPA-TYPE, KA-TYPE AND NMDA RECEPTORS) IN THE RAT SPINAL-CORD WITH SPECIAL REFERENCE TO NOCICEPTION
复制标题
DOI：
10.1016/0169-328x(93)90183-p
复制
发表时间：
1993-04-01
期刊：
影响因子：
--
通讯作者：
TOHYAMA, M
中科院分区：
文献类型：
--
作者：
FURUYAMA, T;KIYAMA, H;TOHYAMA, M
本研究试图探索α-氨基-3-羟基-5-甲基-4-异恶唑丙酸（AMPA）型受体亚基（GluR 1 -4）、红藻氨酸（KA）型受体亚基（GluR 5）、NR 1 [N-甲基-D-天冬氨酸（NMDA）受体的亚单位]和可能的谷氨酸-用原位杂交组织化学方法观察大鼠脊髓背角NMDA受体复合物结合亚基的变化。这些结果与脊髓运动神经元的结果进行了比较。AMPA型受体的亚单位的表达也进行了检查，在蛋白质水平上使用免疫细胞化学，参照运动神经元。虽然AMPA型受体的所有四个亚基在整个背角表达，但表达模式根据背角区域和亚基而不同。GluR 2在脊髓背角表达最强。大量的强标记细胞形成了一个密集的收集在第二层和第三层的浅表部分。许多神经元在第二层和第三层的浅表部分表达GluR 1中度。在这些区域中还观察到散在的中等表达GluR 3的神经元，而GluR 4的表达非常低。标记的背角神经元的GluR 5探针是低的，NR 1探针和谷氨酸结合亚基的NMDA受体复合物探针标记他们弥漫低至中等强度。这些研究结果表明，谷氨酸能伤害性初级传入系统和AMPA型受体之间的密切关系，其中GluR 2是特别高的表达。本研究进一步表明，谷氨酸受体在脊髓感觉神经元和脊髓运动神经元的表达模式有很大的不同，运动神经元非常强烈地表达GluR 3和4，而GluR 2和GluR 1分别是中等和低表达。GluR 5在运动神经元中的表达也较低。然而，NR 1和NMDA受体复合物的谷氨酸结合亚基的表达非常强。这些结果表明，AMPA型受体调节运动神经元的亚基组成与脊髓感觉神经元中的AMPA型受体不同，并且至少存在两种类型的谷氨酸能系统调节运动神经元：通过AMPA型受体和通过NMDA受体。
The present study attempted to explore the gene expression of the subunits (GluR1-4) of the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-type receptor, subunit (GluR5) of kainic acid (KA)-type receptor, NR1 [a subunit of N-methyl-D-aspartate (NMDA) receptors] and the possible glutamate-binding subunit of an NMDA receptor complex in the dorsal horn of the rat spinal cords using in situ hybridization histochemistry. These results were compared with those of the spinal motor neurons. Expression of the subunits of the AMPA-type receptor was also examined at the protein level using immunocytochemistry, with reference to the motor neurons. Although all the four subunits of the AMPA-type receptor were expressed throughout the dorsal horn, the pattern of expression was different according to the dorsal horn region and to the subunits. GluR2 showed the strongest expression in the dorsal horn. Huge numbers of strongly labelled cells formed a dense collection in lamina II and superficial parts of lamina III. Many neurons in lamina II and superficial parts of lamina III expressed GluR1 moderately. Scattered neurons moderately expressing GluR3 were also seen in these regions, while the expression of GluR4 was very low. Labelling of the dorsal horn neurons by the GluR5 probe was low, and NR1 probe and a glutamate-binding subunit of an NMDA receptor complex probe labelled them diffusely with low to moderate intensity. These findings show a close relationship between the glutamergic nociceptive primary afferent system and AMPA-type receptors in which GluR2 is especially highly expressed. The present study further showed that the expression pattern of the glutamate receptors in the spinal sensory neurons differs considerably from that of spinal motor neurons, Motor neurons very strongly express GluR3 and 4, while the expression of GluR2 and GluR1 is moderate and low, respectively. Expression of GluR5 is also low in the motor neurons. However, expression of NR1 and the glutamate-binding subunit of an NMDA receptor complex is very strong. These findings indicate that the subunit composition of the AMPA-type receptors regulating motor neurons is different from that of the AMPA-type receptors in the spinal sensory neurons, and that there are at least two kinds of glutamergic systems which regulate motor neurons: via AMPA-type receptors and via NMDA receptors.