title: Effects on breathing of agonists to μ-opioid or GABAAreceptors dialyzed into the ventral respiratory column of awake and sleeping goats.
abstract: Pulmonary ventilation (V̇I) in awake and sleeping goats does not change when antagonists to several excitatory G protein-coupled receptors are dialyzed unilaterally into the ventral respiratory column (VRC). Concomitant changes in excitatory neuromodulators in the effluent mock cerebral spinal fluid (mCSF) suggest neuromodulatory compensation. Herein, we studied neuromodulatory compensation during dialysis of agonists to inhibitory G protein-coupled or ionotropic receptors into the VRC. Microtubules were implanted into the VRC of goats for dialysis of mCSF mixed with agonists to either μ-opioid (DAMGO) or GABAA(muscimol) receptors. We found: (1) V̇Idecreased during unilateral but increased during bilateral dialysis of DAMGO, (2) dialyses of DAMGO destabilized breathing, (3) unilateral dialysis of muscimol increased V̇I,and (4) dialysis of DAMGO decreased GABA in the effluent mCSF. We conclude: (1) neuromodulatory compensation can occur during altered inhibitory neuromodulator receptor activity, and (2) the mechanism of compensation differs between G protein-coupled excitatory and inhibitory receptors and between G protein-coupled and inotropic inhibitory receptors.
authors.affiliation: Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53226, United States.
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Langer
authors.affiliation: Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53226, United States.
authors.forename: Suzanne E
authors.initials: SE
authors.lastname: Neumueller
authors.affiliation: Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53226, United States.
authors.forename: Emma
authors.initials: E
authors.lastname: Crumley
authors.affiliation: Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53226, United States.
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: Burgraff
authors.affiliation: Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53226, United States.
authors.forename: Sawan
authors.initials: S
authors.lastname: Talwar
authors.affiliation: Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53226, United States; Neuroscience Research Center, Medical College of Wisconsin, Milwaukee, WI 53226, United States.
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Hodges
authors.affiliation: Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53226, United States; Department of Physical Therapy, Marquette University, Milwaukee, WI 53226, United States.
authors.forename: Lawrence
authors.initials: L
authors.lastname: Pan
authors.affiliation: Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53226, United States; Neuroscience Research Center, Medical College of Wisconsin, Milwaukee, WI 53226, United States; Zablocki Veterans Affairs Medical Center, Milwaukee, WI 53226, United States. Electronic address: bforster@mcw.edu.
authors.forename: Hubert V
authors.initials: HV
authors.lastname: Forster
mesh_terms: D000701:Analgesics, Opioid / Q000494:pharmacology*; D000818:Animals; D003956:Dialysis / Q000379:methods; D004305:Dose-Response Relationship, Drug; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)- / Q000494:pharmacology*; D005260:Female; D007839:Functional Laterality / Q000187:drug effects; D058785:GABA-A Receptor Agonists / Q000494:pharmacology*; D006041:Goats; D009118:Muscimol / Q000494:pharmacology*; D018377:Neurotransmitter Agents / Q000378:metabolism; D012119:Respiration / Q000187:drug effects*; D012125:Respiratory Center / Q000187:drug effects* / Q000502:physiology; D012890:Sleep / Q000187:drug effects; D014851:Wakefulness / Q000187:drug effects
chemical_list: D000701:Analgesics, Opioid; D058785:GABA-A Receptor Agonists; D018377:Neurotransmitter Agents; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; D009118:Muscimol
keywords: Breathing; GABA(A); Neuromodulation; Sleep; Ventral respiratory column; μ-Opioids