Vesicular glutamate transporters type 1 and 2 expression in axon terminals of the rat nucleus of the solitary tract.

Abstract:

:The nucleus of the solitary tract is the site of termination of primary afferent fibers running in the facial, glossopharyngeal and vagus nerves. The present study was performed to map the distribution of glutamatergic axons terminals in the rat nucleus of the solitary tract using immunodetection of vesicular glutamate transporter 1 and vesicular glutamate transporter 2. The two vesicular glutamate transporters were differentially distributed among nucleus of the solitary tract subdivisions. Vesicular glutamate transporter 1 immunoreactivity was mostly found in the lateral part of the nucleus (ventrolateral, interstitial and intermediate subdivisions) whereas vesicular glutamate transporter 2 labeling was distributed throughout the nucleus of the solitary tract. Electron microscope examination indicated that vesicular glutamate transporter immunoreactivity was localized in axon terminals filled with round synaptic vesicles. After injection of cholera toxin B subunit in sensory ganglia, anterograde labeling was found in vesicular glutamate transporter 1, as well as vesicular glutamate transporter 2-immunoreactive boutons. Double immunolabeling experiments allowed distinctions between terminals expressing either vesicular glutamate transporter 1 or vesicular glutamate transporter 2 or both vesicular glutamate transporter 1 and vesicular glutamate transporter 2 immunoreactivities. The latter population, expressing both transporters immunolabeling, completely disappeared after deafferentation induced by removal of sensory ganglia. This study indicates that vesicular glutamate transporter content identifies three different subpopulations of glutamatergic boutons in the nucleus of the solitary tract and provides definitive evidence that primary afferent neurons contribute glutamatergic terminals to the nucleus of the solitary tract.

journal_name

Neuroscience

journal_title

Neuroscience

authors

Lachamp P,Crest M,Kessler JP

doi

10.1016/j.neuroscience.2005.08.048

keywords:

subject

Has Abstract

pub_date

2006-01-01 00:00:00

pages

73-81

issue

1

eissn

0306-4522

issn

1873-7544

pii

S0306-4522(05)00939-5

journal_volume

137

pub_type

杂志文章