三叉神经脊束间质核内一氧化氮参与内脏伤害性信息传递的实验观察

摘要

背景:一氧化氮合酶(nitric oxide synthase,OS)广泛分布于中枢神经系统并调节神经活动,但鲜见在中枢神经脊上水平有关NOS参与内脏神经传入信息传递的报道.目的:探查三叉神经脊束间质核(interstitial nucleus of trigeminal tract.INV)内内脏传入终末与向臂旁核(parabrachial nucleus,BN)投射的NOS阳性神经元之间的联系.设计:以实验动物为研究对象,验证性对比观察.单位:一所军医大学解剖学教研室.材料:选择成年SD雄性大鼠10只进行动物试验.干预:分别给PBN及舌咽和迷走神经内注射四甲基罗丹明(tetramethvl rhodamine-dextran,MR),生物素化葡聚糖胺(biotinylated dextran-amine.BDA)并进行NOS免疫组织化学反应,结合激光扫描共聚焦显微镜观察.主要观察指标:观察逆行TMR标记细胞、NOS阳性细胞以及跨神经节BDA标记的传入终末在INV内的重叠分布和三者的相互关系.结果:逆行标记细胞主要位于注射侧的INV,大多属20μm以下的中、小型细胞.NOS阳性细胞与TMR逆行标记细胞分布区域重叠.计数显不:NOS/TMR双标记细胞分别占NOS阳性细胞总数的55%(17/31)和TMR逆行标记细胞总数的34%(17/49).跨神经节注射BDA标记的内脏神经初级传入终末点状膨体贴近双标记细胞胞体,呈紧密接触状.结论:存在经INV向PBN投射的内脏信息传导通路,作为神经递质和神经信息分子的一氧化氮可能参与其内脏伤害性信息的传递和调控.%BACKGROUND: Nitric oxide synthase(NOS) is extensively distributed in the central nervous system and modulates neuronal activities. However,there are few reports about NOS' s involvement in nociceptive information transmission at the supraspinal level.OBJECTIVE: To investigate the relation between the primary afferent visceral terminials and the NOS-containing neurons which project from the interstitial nucleus of spinal trigeminal tract(INV) to the parabrachial nucleus(PBN).DESIGN: A controlled experimental observation based on the experimental animals.SETTING: Department of anatomy in a military medical university of Chinese PLA.MATERIALS: The experiment was conducted in the Department of Anatomy,Fourth Military Medical University of Chinese PLA,from January to December 2002. Ten adult male SD rats were selected in this experiment.INTERVENTIONS: Tetramethyl rhodamine-dextran(TMR) and biotinylated dextran-amine(BDA) were injected into the PBN and vago-glossopharyngeal nerves respectively combining with the immunohistochemical method for NOS and the observation with laser confocal scanning microscope.MAIN OUTCOME MEASUREES: Overlapping of TMR retrogradely labeled neurons,NOS positive labeled neurons and transganglionic tracing labeled terminals,and their relationship in INV.RESULTS: After injection of TMR into the PBN,the retrogradely labeled neurons,mostly small and medium-sized(below20 μm),were found in the INV ipsilateral to the injection side. The distribution of the NOS positive neurons overlapped with retrogradely labeled neurons in INV. The proportion of the number of double-labeled neurons with NOS/TMR was 55% (17/31)and 34% (17/49) in the whole population of the NOS positive neurons and retrogradely neurons,respectively. Some transganglionic tracing labeled terminals after BDA injection had close contact with the double-labeled neurons.CONCLUSION: The visceral nociceptive pathway exists from INV to PBN and NO may act as the transmitter or neural signal molecule in the transmission and regulation of visceral nociceptive process.