Berthoud H R, Powley T L
Pennington Biomedical Research Center, Louisiana State University, Baton Rouge 70808 USA.
Microsc Res Tech. 1996 Sep 1;35(1):80-6. doi: 10.1002/(SICI)1097-0029(19960901)35:1<80::AID-JEMT7>3.0.CO;2-W.
Vagal efferent preganglionic neurons were anterogradely labeled by injecting either DiI or DiA, fluorescent lipophilic carbocyanine dyes, into the dorsal motor nucleus of the vagus of the rat. All neurons of the peripheral nervous system (outside the blood-brain barrier) were then fluorescently counterstained in vivo by injecting Fluorogold (Fluorochrome, Inc., Englewood, CO) intraperitoneally. The upper abdominal prevertebral ganglia, including the numerous microganglia associated with the periarterial plexuses of the celiac and superior mesenteric arteries, were identified and dissected in formalin-fixed tissue under ultraviolet light and stereomicroscopic guidance. In 14 of 15 animals analyzed (93%), labeled vagal efferent fibers were found to penetrate into both the left and right celiac ganglia and the superior mesenteric ganglion, as well as into some of the associated microganglia. These projections formed varicose terminal-like structures, highly suggestive of synaptic contacts surrounding individual ganglion cells. In about half the animals, such vagal innervation was also seen in the left and right suprarenal ganglia. The specificity of vagal efferent labeling was confirmed by control experiments, which included injections in vagotomized animals and direct selective labeling of vagal afferents from the nodose ganglia. It is concluded that vagal efferent preganglionics innervate principal ganglion cells of prevertebral ganglia. These vagal contacts may either directly modulate the postganglionic outflow or else gate some or all of the potential modulatory inputs to these postganglionic neurons, thus allowing the vagal system to exert a more selective influence on sympathetic outflow. Finally, the use of laser scanning confocal microscopy and the in toto Fluorogold staining method for investigations of the peripheral nervous system are discussed.
通过将亲脂性荧光碳青霉烯染料碘化丙啶（DiI）或二苯甲酰胺（DiA）注射到大鼠迷走神经背核中，对迷走神经传出节前神经元进行顺行标记。然后通过腹腔注射荧光金（Fluorochrome公司，科罗拉多州恩格尔伍德），在体内对周围神经系统（血脑屏障之外）的所有神经元进行荧光复染。在紫外光和立体显微镜引导下，在福尔马林固定的组织中识别并解剖上腹部椎前神经节，包括与腹腔动脉和肠系膜上动脉的动脉周围丛相关的众多微神经节。在分析的15只动物中的14只（93%）中，发现标记的迷走神经传出纤维穿透到左右腹腔神经节和肠系膜上神经节以及一些相关的微神经节中。这些投射形成了曲张的终末样结构，强烈提示围绕单个神经节细胞的突触联系。在大约一半的动物中，在左右肾上腺神经节中也观察到这种迷走神经支配。对照实验证实了迷走神经传出标记的特异性，对照实验包括在迷走神经切断的动物中注射以及直接选择性标记来自结节神经节的迷走神经传入纤维。得出的结论是，迷走神经传出节前神经元支配椎前神经节的主要神经节细胞。这些迷走神经联系可能直接调节节后传出，或者 else 门控对这些节后神经元的一些或所有潜在调节输入，从而使迷走神经系统对交感神经传出发挥更具选择性的影响。最后，讨论了使用激光扫描共聚焦显微镜和全荧光金染色方法研究周围神经系统。
