title: Specific neural substrate linking respiration to locomotion.
abstract: When animals move, respiration increases to adapt for increased energy demands; the underlying mechanisms are still not understood. We investigated the neural substrates underlying the respiratory changes in relation to movement in lampreys. We showed that respiration increases following stimulation of the mesencephalic locomotor region (MLR) in an in vitro isolated preparation, an effect that persists in the absence of the spinal cord and caudal brainstem. By using electrophysiological and anatomical techniques, including whole-cell patch recordings, we identified a subset of neurons located in the dorsal MLR that send direct inputs to neurons in the respiratory generator. In semi-intact preparations, blockade of this region with 6-cyano-7-nitroquinoxaline-2,3-dione and (2R)-amino-5-phosphonovaleric acid greatly reduced the respiratory increases without affecting the locomotor movements. These results show that neurons in the respiratory generator receive direct glutamatergic connections from the MLR and that a subpopulation of MLR neurons plays a key role in the respiratory changes linked to movement.
authors.affiliation: Central Nervous System Research Group, Department of Physiology, Université de Montréal, Montréal, QC, Canada H3T 1J4.
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Gariépy
authors.forename: Kianoush
authors.initials: K
authors.lastname: Missaghi
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Chevallier
authors.forename: Shannon
authors.initials: S
authors.lastname: Chartré
authors.forename: Maxime
authors.initials: M
authors.lastname: Robert
authors.forename: François
authors.initials: F
authors.lastname: Auclair
authors.forename: James P
authors.initials: JP
authors.lastname: Lund
authors.forename: Réjean
authors.initials: R
authors.lastname: Dubuc
mesh_terms: D015763:2-Amino-5-phosphonovalerate / Q000494:pharmacology; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione / Q000494:pharmacology; D000818:Animals; D004558:Electric Stimulation; D004594:Electrophysiology; D006652:Histological Techniques; D066298:In Vitro Techniques; D007798:Lampreys / Q000502:physiology*; D008124:Locomotion / Q000502:physiology*; D008636:Mesencephalon / Q000502:physiology*; D009434:Neural Pathways; D009474:Neurons / Q000502:physiology; D010101:Oxygen Consumption / Q000187:drug effects / Q000502:physiology*; D018408:Patch-Clamp Techniques; D014741:Video Recording
chemical_list: D018750:6-Cyano-7-nitroquinoxaline-2,3-dione; D015763:2-Amino-5-phosphonovalerate