Kraus T, Neuhuber W L, Raab M
Department of Anatomy I, University of Erlangen-Nuremberg, Erlangen, Germany.
Cell Tissue Res. 2007 Aug;329(2):205-19. doi: 10.1007/s00441-007-0392-8. Epub 2007 May 17.
In rat and mouse esophagus, vesicular glutamate transporter 2 (VGLUT2) has been demonstrated to identify vagal intraganglionic laminar endings (IGLEs); this has recently also been shown for VGLUT1 in rat esophagus. In this study, we have investigated the distribution of VGLUT1 in the mouse esophagus and compared these results with the recently published data from the rat esophagus. Unexpectedly, we have discovered that VGLUT1 mostly fails to identify IGLEs in the mouse esophagus. This is surprising, since the distribution of VGLUT2 shows comparable results in both species. Confocal imaging has revealed substantial colocalization of VGLUT1 immunoreactivity (-ir) with cholinergic and nitrergic/peptidergic markers within the myenteric neuropil and in both cholinergic and nitrergic myenteric neuronal cell bodies. VGLUT1 and cholinergic markers have also been colocalized in fibers of the muscularis mucosae, whereas VGLUT1 and nitrergic markers have never been colocalized in fibers of the muscularis mucosae, although this does occur in fibers of the muscularis running to motor endplates. Thus, VGLUT1 is contained in the nitrergic innervation of mouse esophageal motor endplates, another difference from the rat esophagus. VGLUT1-ir is therefore present in extrinsic and intrinsic innervation of the mouse esophagus, but the significant differences from the rat indicate species variations concerning the distribution of VGLUTs in the peripheral nervous system.
在大鼠和小鼠的食管中，囊泡型谷氨酸转运体2（VGLUT2）已被证实可识别迷走神经节内分层终末（IGLEs）；最近在大鼠食管中也发现VGLUT1有此作用。在本研究中，我们调查了VGLUT1在小鼠食管中的分布，并将这些结果与最近发表的大鼠食管数据进行了比较。出乎意料的是，我们发现VGLUT1在小鼠食管中大多无法识别IGLEs。这很令人惊讶，因为VGLUT2在这两个物种中的分布结果具有可比性。共聚焦成像显示，在肌间神经丛内以及胆碱能和一氧化氮能/肽能肌间神经元细胞体中，VGLUT1免疫反应性（-ir）与胆碱能和一氧化氮能标记物有大量共定位。VGLUT1和胆碱能标记物也在黏膜肌层的纤维中共定位，而VGLUT1和一氧化氮能标记物在黏膜肌层的纤维中从未共定位，尽管在通向运动终板的肌层纤维中会出现这种情况。因此，VGLUT1存在于小鼠食管运动终板的一氧化氮能神经支配中，这是与大鼠食管的另一个差异。因此，VGLUT1-ir存在于小鼠食管的外在和内在神经支配中，但与大鼠的显著差异表明在周围神经系统中VGLUTs的分布存在物种差异。
