Glutamatergic vestibular neurons express Fos after vestibular stimulation and project to the NTS and the PBN in rats.
In this study, retrograde tracing method combined with phosphate-activated glutaminase (PAG) and Fos immunofluorescence histochemistry was used to identify glutamatergic vestibular nucleus (VN) neurons receiving vestibular inputs and projecting to the nucleus of the solitary tract (NTS) and the parabrachial nucleus (PBN). Conscious animals were subjected to 120 min Ferris-wheel like rotation stimulation. Neuronal activation was assessed by Fos expression in the nucleus of VN neurons. After Fluoro-gold (FG) injection into the caudal NTS, approximately 48% FG-labeled VN neurons were immunoreactive for PAG, and about 14% PAG/FG double-labeled neurons co-existed with Fos. Following FG injection into the PBN, approximately 56% FG-labeled VN neurons were double-labeled with PAG, and about 12% of the PAG/FG double-labeled neurons also expressed Fos. Careful examination of the typology and distribution pattern of these PAG-immunoreactive neurons indicated that the vast majority of these neurons were glutamatergic rather than GABAergic. These results suggest that PAG-immunoreactive VN neurons might constitute excitatory glutamatergic VN-NTS and VN-PBN transmission pathways and these pathways might be involved in vestibulo-autonomic reflexes during vestibular stimulation.
Cai
Yi-Ling
YL
Department of Military Hygiene, Faculty of Naval Medicine, Second Military Medical University, Shanghai 200433, PR China. yilingcai1@sohu.com
Ma
Wen-Ling
WL
Li
Min
M
Guo
Jun-Sheng
JS
Li
Yi-Qian
YQ
Wang
Li-Gang
LG
Wang
Wei-Zhong
WZ
D000818:Animals; D017776:Autonomic Pathways / Q000033:anatomy & histology / Q000378:metabolism*; D001931:Brain Mapping; D018698:Glutamic Acid / Q000378:metabolism*; D007150:Immunohistochemistry; D008297:Male; D009041:Motion Sickness / Q000378:metabolism / Q000503:physiopathology; D011149:Pons / Q000033:anatomy & histology / Q000378:metabolism*; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D012399:Rotation; D017552:Solitary Nucleus / Q000033:anatomy & histology / Q000378:metabolism*; D013266:Stilbamidines; D009435:Synaptic Transmission / Q000502:physiology; D014726:Vestibular Nuclei / Q000033:anatomy & histology / Q000378:metabolism*; D014722:Vestibule, Labyrinth / Q000502:physiology*; D017833:Visceral Afferents / Q000166:cytology / Q000378:metabolism
C049774:2-hydroxy-4,4'-diamidinostilbene, methanesulfonate salt; D016760:Proto-Oncogene Proteins c-fos; D013266:Stilbamidines; D018698:Glutamic Acid