NMDA受体与NOS在大鼠脊髓中间外侧柱的定位和生后发育

目的 探讨N-甲基-天冬氨酸受体（NMDAR1和NMDAR2A/B亚基）、一氧化氮合酶（NOS）及还原型辅酶Ⅱ硫辛酰胺脱氢酶（NADPH-d）活性在大鼠脊髓中间外侧柱（IML）的定位与生后发育特征。方法 在甲醛固定的脊髓切片上,进行ABC法免疫染色和NADPH-d组织化学反应与半定量分析。结果 MMDAR1,NMDAR2A/B,NOS I和NADPH-d反应产物丰富地分布于IML,主要定位于神经元胞体、树突和轴突样纤维终末。在生后早期发育中它们具有明显的动态变化,生后7d(P7）有微弱或中等的表达,随后逐渐上调,P21或P28达到高峰,然后保持于此水平于成体动物。结论 NMDA受体-NO通路可能是脊髓交感节前神经元一条重要的细胞内信号途径,并参与神经元生后发育成熟的调控过程。

Localization and postnatal development of NMDA receptors and NOS in intermediolateral column of spinal cord of adult rats

AIM To investigate the cellular localization and early postnatal development of N methyl aspartate (NMDA) receptor subunits (NMDAR1 and NMDAR2A/B), nitric oxide synthase (NOS) and NADPH diaphorase activity in the intermediolateral column (IML) of the spinal cord in adult rats. METHODS ABC immunohistochemical staining and NADPH d histochemistry were made in paraformaldehyde fixed spinal cord sections. RESULTS NMDAR1 , NMDAR2A/B , NOSI immunoreactivity, or NADPH diaphorase activity was abundant in IML. They were mainly located in neuronal somata, dendrites and axon terminals. Dynamic changes of NMDA receptor subunits, NOS and NADPH d activity occurred in early postnatal developing stages. Expression of NMDA receptor subunits and NOSI was weak or moderate at postnatal 7 days (P7), went up at P14, reached maximum level at P21 or P28, then remained stable at this level until adult. CONCLUSION NMDA receptor NO may be an important intracellular signal pathway of pre sympathetic neurons and involved in the neuronal maturation during postnatal development of rat spinal cord.