Vesicular glutamate transporter 1 immunoreactivity in motor endplates of striated esophageal but not skeletal muscles in the mouse

doi:10.1016/j.neulet.2004.02.039

Neuroscience Letters

Volume 360, Issues 1–2, 22 April 2004, Pages 53-56

https://doi.org/10.1016/j.neulet.2004.02.039 Get rights and content

Abstract

Glutamate, the major excitatory transmitter in the central nervous system, has been speculated for years to influence mammalian motor endplates but trials to identify glutamatergic motor terminals failed because specific markers were not available. Recently, antibodies to vesicular glutamate transporters (VGLUTs) opened new possibilities for further morphological investigations. We detected VGLUT1 immunoreactivity (-ir), but not VGLUT2-ir and VGLUT3-ir, respectively, in many motor nerve terminals in motor endplates of the mouse esophagus as identified by α-bungarotoxin or colocalization of VGLUT1 with choline acetyltransferase. These findings suggest that glutamate is co-stored with acetylcholine in esophageal neuromuscular junctions. Surprisingly, we found neither VGLUT1-ir nor VGLUT2-ir or VGLUT3-ir in neuromuscular junctions of somitic and branchiogenic skeletal muscles. This may reflect differences in functional properties and the embryonic origin between skeletal and esophageal striated muscle fibers.

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Acknowledgements

The technical assistance of Karin Löschner, Anita Hecht, Hedwig Symowski, Stefanie Link, Andrea Hilpert and Inge Zimmermann is gratefully acknowledged. We especially thank J. Wörl for providing the mice. This study was supported by Johannes und Frieda Marohn-Stiftung, Erlangen.

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Vesicular glutamate transporter 1 immunoreactivity in motor endplates of striated esophageal but not skeletal muscles in the mouse

Abstract

Section snippets

Acknowledgements

Neurochem. Int.

Neuroscience

Neurosci. Lett.

Brain Res. Bull.

Neurosci. Lett.

Uptake of glutamate into synaptic vesicles by an inorganic phosphate transporter

Science

Viscerotopic representation of the upper alimentary tract in the medulla oblongata in the rat: the nucleus ambiguus

J. Comp. Neurol.

The identification of vesicular glutamate transporter 3 suggests novel modes of signaling by glutamate

Proc. Natl. Acad. Sci. USA

Coexistence of glutamate and acetylcholine in the developing motoneurons

Chin. J. Physiol.

Co-localization of nitric oxide synthase I (NOS I) and NMDA receptor subunit 1 (NMDAR-1) at the neuromuscular junction in rat and mouse skeletal muscle

Cell Tissue Res.