Parabrachial-lateral pontine neurons link nociception and breathing.
We investigated the role of the parabrachial complex in cutaneous nociceptor-induced respiratory stimulation in chloralose-urethane anesthetized, vagotomized rats. Noxious stimulation (mustard oil, MO) applied topically to a forelimb or hindlimb enhanced the peak amplitude of the integrated phrenic nerve discharge and, with forelimb application, increased phrenic nerve burst frequency. Bilateral inactivation of neural activity in the parabrachial complex with injection of the GABA agonist muscimol (3nl) markedly attenuated the response to MO application. Injection of the retrograde tracer FluoroGold within the medullary ventral respiratory column labeled neurons in dorsolateral pontine regions known to receive nociceptive inputs (i.e., Kolliker-Fuse, lateral crescent, and superior lateral subnuclei of the parabrachial complex). Extracellular recordings of 65 dorsolateral parabrachial neurons revealed about 15% responded to a noxious cutaneous pinch with either an increase or a decrease in discharge and approximately 40% of these exhibited a phasic respiratory-related component to their discharge. In conclusion, parabrachial pontine neurons contribute to cutaneous nociceptor-induced increases in breathing.
Jiang
Mingchen
M
Department of Physiology and Institute for Neuroscience, Feinberg School of Medicine, Northwestern University, M211, 303 E. Chicago Ave., Chicago, IL 60611-3008, USA.
Alheid
George F
GF
Calandriello
Tara
T
McCrimmon
Donald R
DR
D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000818:Animals; D001931:Brain Mapping; D004334:Drug Administration Schedule; D005121:Extremities / Q000294:innervation / Q000528:radiation effects; D005456:Fluorescent Dyes / Q000378:metabolism; D018755:GABA Agonists / Q000494:pharmacology; D008297:Male; D008526:Medulla Oblongata / Q000166:cytology / Q000187:drug effects / Q000502:physiology* / Q000503:physiopathology; D009118:Muscimol / Q000494:pharmacology; D009149:Mustard Plant; D009434:Neural Pathways / Q000187:drug effects / Q000502:physiology / Q000503:physiopathology*; D009474:Neurons / Q000502:physiology*; D010146:Pain / Q000139:chemically induced / Q000503:physiopathology*; D010147:Pain Measurement / Q000379:methods; D010791:Phrenic Nerve / Q000187:drug effects / Q000503:physiopathology; D010812:Physical Stimulation / Q000379:methods; D011149:Pons / Q000166:cytology* / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012119:Respiration; D013194:Staining and Labeling / Q000379:methods; D013266:Stilbamidines / Q000378:metabolism; D014628:Vagotomy / Q000379:methods
C049774:2-hydroxy-4,4'-diamidinostilbene, methanesulfonate salt; D005456:Fluorescent Dyes; D018755:GABA Agonists; D013266:Stilbamidines; D009118:Muscimol