Document Type
Article
Language
eng
Publication Date
8-1-2015
Publisher
American Physiological Society
Source Publication
Journal of Applied Physiology
Source ISSN
0021-8987
Original Item ID
DOI: 10.1152/japplphysiol.00145.2015
Abstract
Previous work in intact awake and sleeping goats has found that unilateral blockade of excitatory inputs in the ventral respiratory column (VRC) elicits changes in the concentrations of multiple neurochemicals, including serotonin (5-HT), substance P, glycine, and GABA, while increasing or having no effect on breathing. These findings are consistent with the concept of interdependence between neuromodulators, whereby attenuation of one modulator elicits compensatory changes in other modulators to maintain breathing. Because there is a large degree of redundancy and multiplicity of excitatory inputs to the VRC, we herein tested the hypothesis that combined unilateral blockade of muscarinic acetylcholine (mACh), neurokinin-1 (NK1, the receptor for substance P), and 5-HT2A receptors would elicit changes in multiple neurochemicals, but would not change breathing. We unilaterally reverse-dialyzed a cocktail of antagonists targeting these receptors into the VRC of intact adult goats. Breathing was continuously monitored while effluent fluid from dialysis was collected for quantification of neurochemicals. We found that neither double blockade of mACh and NK1 receptors, nor triple blockade of mACh, NK1, and 5-HT2A receptors significantly affected breathing (P ≥ 0.05) in goats that were awake or in non-rapid eye movement (NREM) sleep. However, both double and triple blockade increased the effluent concentration of substance P (P < 0.001) and decreased GABA concentrations. These findings support our hypothesis and, together with past data, suggest that both in wakefulness and NREM sleep, multiple neuromodulator systems collaborate to stabilize breathing when a deficit in one or multiple excitatory neuromodulators exists.
Recommended Citation
Muere, Clarissa; Neumueller, Suzanne; Olesiak, Samantha; Miller, Justin Robert; Langer, Thomas; Hodges, Matthew; Pan, Lawrence; and Forster, Hubert, "Combined Unilateral Blockade of Cholinergic, Peptidergic, And Serotonergic Receptors in The Ventral Respiratory Column Does Not Affect Breathing in Awake Or Sleeping Goats" (2015). Physical Therapy Faculty Research and Publications. 96.
https://epublications.marquette.edu/phys_therapy_fac/96
Comments
Accepted version. Journal of Applied Physiology, Vol. 119, No. 3 (August 1, 2015): 308-320. DOI. © 2015 The American Physiological Society. Used with permission.