Investigation of vagal sensory neurons in mice using optical vagal stimulation and tracheal neuroanatomy
Aung Aung Kywe Moe,
Tara G. Bautista,
Matthew W. Trewella,
Willian S. Korim,
Song T. Yao,
Robert Behrens,
Alexandria K. Driessen,
Alice E. McGovern,
Stuart B. Mazzone
Affiliations
Aung Aung Kywe Moe
Department of Anatomy and Physiology, School of Biomedical Sciences, The University of Melbourne, Parkville, VIC 3010, Australia; Department of Medical Imaging and Radiation Sciences, School of Primary and Allied Health Care, Monash University, Clayton Campus, Clayton, VIC 3800, Australia
Tara G. Bautista
Department of Anatomy and Physiology, School of Biomedical Sciences, The University of Melbourne, Parkville, VIC 3010, Australia
Matthew W. Trewella
Department of Anatomy and Physiology, School of Biomedical Sciences, The University of Melbourne, Parkville, VIC 3010, Australia
Willian S. Korim
Department of Anatomy and Physiology, School of Biomedical Sciences, The University of Melbourne, Parkville, VIC 3010, Australia
Song T. Yao
Department of Anatomy and Physiology, School of Biomedical Sciences, The University of Melbourne, Parkville, VIC 3010, Australia
Robert Behrens
Department of Anatomy and Physiology, School of Biomedical Sciences, The University of Melbourne, Parkville, VIC 3010, Australia
Alexandria K. Driessen
Department of Anatomy and Physiology, School of Biomedical Sciences, The University of Melbourne, Parkville, VIC 3010, Australia
Alice E. McGovern
Department of Anatomy and Physiology, School of Biomedical Sciences, The University of Melbourne, Parkville, VIC 3010, Australia
Stuart B. Mazzone
Department of Anatomy and Physiology, School of Biomedical Sciences, The University of Melbourne, Parkville, VIC 3010, Australia; Corresponding author
Summary: In rats and guinea pigs, sensory innervation of the airways is derived largely from the vagus nerve, with the extrapulmonary airways innervated by Wnt1+ jugular neurons and the intrapulmonary airways and lungs by Phox2b+ nodose neurons; however, our knowledge of airway innervation in mice is limited. We used genetically targeted expression of enhanced yellow fluorescent protein-channelrhodopsin-2 (EYFP-ChR2) in Wnt1+ or Phox2b+ tissues to characterize jugular and nodose-mediated physiological responses and airway innervation in mice. With optical stimulation, Phox2b+ vagal fibers modulated cardiorespiratory function in a frequency-dependent manner while right Wnt1+ vagal fibers induced a small increase in respiratory rate. Mouse tracheae contained sparse Phox2b-EYFP fibers but dense networks of Wnt1-EYFP fibers. Retrograde tracing from the airways showed limited tracheal innervation by the jugular sensory neurons, distinct from other species. These differences in physiology and vagal sensory distribution have important implications when using mice for studying airway neurobiology.
