title: Specific activation of the paralemniscal pathway during nociception.
abstract: Two main neuronal pathways connect facial whiskers to the somatosensory cortex in rodents: (i) the lemniscal pathway, which originates in the brainstem principal trigeminal nucleus and is relayed in the ventroposterior thalamic nucleus and (ii) the paralemniscal pathway, originating in the spinal trigeminal nucleus and relayed in the posterior thalamic nucleus. While lemniscal neurons are readily activated by whisker contacts, the contribution of paralemniscal neurons to perception is less clear. Here, we functionally investigated these pathways by manipulating input from the whisker pad in freely moving mice. We report that while lemniscal neurons readily respond to neonatal infraorbital nerve sectioning or whisker contacts in vivo, paralemniscal neurons do not detectably respond to these environmental changes. However, the paralemniscal pathway is specifically activated upon noxious stimulation of the whisker pad. These findings reveal a nociceptive function for paralemniscal neurons in vivo that may critically inform context-specific behaviour during environmental exploration.
authors.affiliation: Department of Basic Neurosciences, University of Geneva, 1 rue Michel Servet, 1211, Geneva, Switzerland.
authors.forename: Laura
authors.initials: L
authors.lastname: Frangeul
authors.forename: Cesar
authors.initials: C
authors.lastname: Porrero
authors.forename: Maria
authors.initials: M
authors.lastname: Garcia-Amado
authors.forename: Benedetta
authors.initials: B
authors.lastname: Maimone
authors.forename: Madlyne
authors.initials: M
authors.lastname: Maniglier
authors.forename: Francisco
authors.initials: F
authors.lastname: Clascá
authors.forename: Denis
authors.initials: D
authors.lastname: Jabaudon
mesh_terms: D000818:Animals; D051379:Mice; D008810:Mice, Inbred C57BL; D059225:Nociception / Q000502:physiology*; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D014279:Trigeminal Nucleus, Spinal / Q000378:metabolism* / Q000502:physiology; D014738:Vibrissae / Q000294:innervation
chemical_list: D016760:Proto-Oncogene Proteins c-fos
keywords: mouse; sensory physiology; somatosensory cortex; thalamocortical pathways