N-methyl-D-aspartate receptor subunit phenotypes of vagal afferent neurons in nodose ganglia of the rat
N-methyl-D-aspartate receptor subunit phenotypes of vagal afferent neurons in nodose ganglia of the rat
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DOI：
10.1002/cne.20955
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发表时间：
2006-06-20
影响因子：
2.5
通讯作者：
Burns, Gilbert A.
中科院分区：
文献类型：
--
作者：
Czaja, Krzysztof;Ritter, Robert C.;Burns, Gilbert A.
大部分大鼠结状神经节的迷走传入神经元表达编码异聚N-甲基-D-天冬氨酸（NMDA）受体离子通道NR 1亚基的mRNA。NMDA受体亚单位的免疫反应已被检测到的背侧后脑迷走神经传入的轴突末梢，这表明在内脏感觉功能的突触前NMDA受体的作用。虽然NMDA受体亚单位（NR 1，NR 2B，NR 2C和NR 2D）已被链接到不同的神经元群体在大脑中，迷走神经传入神经元的NMDA受体亚单位表型尚未确定。因此，我们研究了NMDA受体亚单位（NR 1，NR 2B，NR 2C和NR 2D）的免疫反应性迷走神经传入神经元。我们发现，虽然左侧结状神经节包含的神经元（7，603个）明显多于右侧（5，978个），但在左侧和右侧结状神经节中表达的NMDA亚基的比例没有显著差异。92.3%的结状核神经元表达NMDAR 1亚单位。NR 2B免疫反应存在于56.7%的神经元; NR 2C表达的结状神经元占总人口的49.4%; NR 2D亚基免疫反应仅在所有结状神经元的13.5%中观察到。双标记显示，30.2%的结状神经元表达NR 213和NR 2C的免疫反应，而NR 2B和NR 2D的免疫反应共定位在11.5%的结状神经元。13.1%的结状核神经元中NR 2C与NR 2D共定位。我们的研究结果表明，大多数迷走神经传入神经元表达NMDA受体离子通道组成的NR 1，NR 2B，和NR 2C亚基和少数表型，表达NR 2D也表达NRI，NR 2B，和NR 2C。
Most vagal afferent neurons in rat nodose ganglia express mRNA coding for the NR1 subunit of the heteromeric N-methyl-D-aspartate (NMDA) receptor ion channel. NMDA receptor subunit immunoreactivity has been detected on axon terminals of vagal afferents in the dorsal hindbrain, suggesting a role for presynaptic NMDA receptors in viscerosensory function. Although NMDA receptor subunits (NR1, NR2B, NR2C, and NR2D) have been linked to distinct neuronal populations in the brain, the NMDA receptor subunit phenotype of vagal afferent neurons has not been determined. Therefore, we examined NMDA receptor subunit (NR1, NR2B, NR2C, and NR2D) immunoreactivity in vagal afferent neurons. We found that, although the left nodose contained significantly more neurons (7,603), than the right (5,978), the proportions of NMDA subunits expressed in the left and right nodose ganglia were not significantly different. Immunoreactivity for NMDA NR1 subunit was present in 92.3% of all nodose neurons. NR2B immunoreactivity was present in 56.7% of neurons; NR2C-expressing nodose neurons made up 49.4% of the total population; NR2D subunit immunoreactivity was observed in just 13.5% of all nodose neurons. Double labeling revealed that 30.2% of nodose neurons expressed immunoreactivity to both NR213 and NR2C, whereas NR2B and NR2D immunoreactivities were colocalized in 11.5% of nodose neurons. NR2C immunoreactivity colocalized with NR2D in 13.1% of nodose neurons. Our results indicate that most vagal afferent neurons express NMDA receptor ion channels composed of NR1, NR2B, and NR2C subunits and that a minority phenotype that expresses NR2D also expresses NRI, NR2B, and NR2C.