title: Activation of state-regulating neurochemical systems in newborn and embryonic chicks.
abstract: Coordinated activity in different sets of widely-projecting neurochemical systems characterize waking (W) and sleep (S). How and when this coordination is achieved during development is not known. We used embryos and newborns of a precocial bird species (chickens) to assess developmental activation in different neurochemical systems using cFos expression, which has been extensively employed to examine cellular activation during S and W in adult mammals. Similarly to adult mammals, newborn awake chicks showed significantly higher cFos expression in W-active hypocretin/orexin (H/O), serotonergic Dorsal Raphe, noradrenergic Locus Coeruleus and cholinergic Laterodorsal and Pedunculopontine Tegmental (Ch-LDT/PT) neurons when compared to sleeping chicks. cFos expression was significantly correlated both between these systems, and with the amount of W. S-active melanin-concentrating hormone (MCH) neurons showed very low cFos expression with no difference between sleeping and awake chicks, possibly due to the very short duration of S episodes. In embryonic chicks, cFos expression was low or absent across all five systems at embryonic day (E) 12. Unexpectedly, a strong activation was seen at E16 in H/O neurons. The highest activation of Ch-LDT/PT (also S-active) and MCH neurons was seen at E20. These data suggest that maturation of arousal systems is achieved soon after hatching, while S-control networks are active in late chick embryos.
authors.affiliation: Department of Psychology, McGill University, Montreal, Quebec H3A 1B1, Canada.
authors.forename: Aimee
authors.initials: A
authors.lastname: Chan
authors.affiliation: Department of Psychology, McGill University, Montreal, Quebec H3A 1B1, Canada.
authors.forename: SiHan
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of Psychology, McGill University, Montreal, Quebec H3A 1B1, Canada.
authors.forename: Ahn R
authors.initials: AR
authors.lastname: Lee
authors.affiliation: Department of Psychology, McGill University, Montreal, Quebec H3A 1B1, Canada.
authors.forename: Joseph
authors.initials: J
authors.lastname: Leung
authors.affiliation: Department of Psychology, McGill University, Montreal, Quebec H3A 1B1, Canada.
authors.forename: Alissa
authors.initials: A
authors.lastname: Yip
authors.affiliation: Department of Psychology, McGill University, Montreal, Quebec H3A 1B1, Canada.
authors.forename: Jaimie
authors.initials: J
authors.lastname: Bird
authors.affiliation: Department of Psychology, McGill University, Montreal, Quebec H3A 1B1, Canada.
authors.forename: Kyle E
authors.initials: KE
authors.lastname: Godden
authors.affiliation: Avian Sleep Group, Max Planck Institute for Ornithology-Seewiesen, Starnberg, Germany.
authors.forename: Dolores
authors.initials: D
authors.lastname: Martinez-Gonzalez
authors.affiliation: Avian Sleep Group, Max Planck Institute for Ornithology-Seewiesen, Starnberg, Germany.
authors.forename: Niels C
authors.initials: NC
authors.lastname: Rattenborg
authors.affiliation: Department of Psychology, McGill University, Montreal, Quebec H3A 1B1, Canada.
authors.forename: Evan
authors.initials: E
authors.lastname: Balaban
authors.affiliation: Department of Psychology, McGill University, Montreal, Quebec H3A 1B1, Canada. Electronic address: maria.pompeiano@mcgill.ca.
authors.forename: Maria
authors.initials: M
authors.lastname: Pompeiano
mesh_terms: D000109:Acetylcholine / Q000378:metabolism; D000818:Animals; D030161:Avian Proteins / Q000378:metabolism; D015153:Blotting, Western; D002642:Chick Embryo; D002645:Chickens; D007028:Hypothalamic Hormones / Q000378:metabolism; D007150:Immunohistochemistry; D008543:Melanins / Q000378:metabolism; D008636:Mesencephalon / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D009638:Norepinephrine / Q000378:metabolism; D000068797:Orexins / Q000378:metabolism; D010907:Pituitary Hormones / Q000378:metabolism; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D011897:Random Allocation; D012701:Serotonin / Q000378:metabolism; D012890:Sleep / Q000502:physiology*; D012892:Sleep Deprivation / Q000378:metabolism / Q000473:pathology; D014851:Wakefulness / Q000502:physiology*
chemical_list: D030161:Avian Proteins; D007028:Hypothalamic Hormones; D008543:Melanins; D000068797:Orexins; D010907:Pituitary Hormones; D016760:Proto-Oncogene Proteins c-fos; D012701:Serotonin; C019463:melanin-concentrating hormone; D000109:Acetylcholine; D009638:Norepinephrine
keywords: cFos; chick embryo; newborn chick; sleep; waking; widely-projecting neurochemical systems