title: The primate pedunculopontine nucleus region: towards a dual role in locomotion and waking state.
abstract: The mesencephalic reticular formation (MRF) mainly composed by the pedunculopontine and the cuneiform nuclei is involved in the control of several fundamental brain functions such as locomotion, rapid eye movement sleep and waking state. On the one hand, the role of MRF neurons in locomotion has been investigated for decades in different animal models, including in behaving nonhuman primate (NHP) using extracellular recordings. On the other hand, MRF neurons involved in the control of waking state have been consistently shown to constitute the cholinergic component of the reticular ascending system. However, a dual control of the locomotion and waking state by the same groups of neurons in NHP has never been demonstrated in NHP. Here, using microelectrode recordings in behaving NHP, we recorded 38 neurons in the MRF that were followed during transition between wakefulness (TWS) and sleep, i.e., until the emergence of sleep episodes characterized by typical cortical slow wave activity (SWA). We found that the MRF neurons, mainly located in the pedunculopontine nucleus region, modulated their activity during TWS with a decrease in firing rate during SWA. Of interest, we could follow some MRF neurons from locomotion to SWA and found that they also modulated their firing rate during locomotion and TWS. These new findings confirm the role of MRF neurons in both functions. They suggest that the MRF is an integration center that potentially allows to fine tune waking state and locomotor signals in order to establish an efficient locomotion.
authors.affiliation: University of Grenoble Alpes, 38000, Grenoble, France.|INSERM, U1216, Grenoble Institut des Neurosciences, 38000, Grenoble, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Goetz
authors.affiliation: University of Grenoble Alpes, 38000, Grenoble, France.|INSERM, U1216, Grenoble Institut des Neurosciences, 38000, Grenoble, France.
authors.forename: Brigitte
authors.initials: B
authors.lastname: Piallat
authors.affiliation: University of Grenoble Alpes, 38000, Grenoble, France.|INSERM, U1216, Grenoble Institut des Neurosciences, 38000, Grenoble, France.
authors.forename: Manik
authors.initials: M
authors.lastname: Bhattacharjee
authors.affiliation: University of Grenoble Alpes, 38000, Grenoble, France.|INSERM, U1216, Grenoble Institut des Neurosciences, 38000, Grenoble, France.|Unité Mixte de Service IRMaGe, Grenoble Alpes Hospital, 38000, Grenoble, France.|Unité Mixte de Service 3552, CNRS, 38000, Grenoble, France.
authors.forename: Hervé
authors.initials: H
authors.lastname: Mathieu
authors.affiliation: University of Grenoble Alpes, 38000, Grenoble, France.|INSERM, U1216, Grenoble Institut des Neurosciences, 38000, Grenoble, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: David
authors.affiliation: University of Grenoble Alpes, 38000, Grenoble, France. SChabardes@chu-grenoble.fr.|INSERM, U1216, Grenoble Institut des Neurosciences, 38000, Grenoble, France. SChabardes@chu-grenoble.fr.|Clinique de neurochirurgie Pôle PALCROS, CHU Grenoble Alpes, 38000, Grenoble, France. SChabardes@chu-grenoble.fr.
authors.forename: Stéphan
authors.initials: S
authors.lastname: Chabardès
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000818:Animals; D001931:Brain Mapping; D002795:Choline O-Acetyltransferase / Q000378:metabolism; D004569:Electroencephalography; D005583:Fourier Analysis; D007091:Image Processing, Computer-Assisted; D008124:Locomotion / Q000502:physiology*; D008252:Macaca fascicularis; D008279:Magnetic Resonance Imaging; D008297:Male; D008839:Microelectrodes; D009474:Neurons / Q000502:physiology; D045042:Pedunculopontine Tegmental Nucleus / Q000000981:diagnostic imaging / Q000378:metabolism / Q000502:physiology*; D012890:Sleep / Q000502:physiology; D014851:Wakefulness / Q000502:physiology*
chemical_list: D002795:Choline O-Acetyltransferase
keywords: Locomotion; Mesencephalic reticular formation; Microelectrode recording; Nonhuman primate; Pedunculopontine nucleus; Waking state