title: The integrative role of orexin/hypocretin neurons in nociceptive perception and analgesic regulation.
abstract: The level of wakefulness is one of the major factors affecting nociception and pain. Stress-induced analgesia supports an animal's survival via prompt defensive responses against predators or competitors. Previous studies have shown the pharmacological effects of orexin peptides on analgesia. However, orexin neurons contain not only orexin but also other co-transmitters such as dynorphin, neurotensin and glutamate. Thus, the physiological importance of orexin neuronal activity in nociception is unknown. Here we show that adult-stage selective ablation of orexin neurons enhances pain-related behaviors, while pharmacogenetic activation of orexin neurons induces analgesia. Additionally, we found correlative activation of orexin neurons during nociception using fiber photometry recordings of orexin neurons in conscious animals. These findings suggest an integrative role for orexin neurons in nociceptive perception and pain regulation.
authors.affiliation: Department of Neuroscience II, Research Institute of Environmental Medicine, Nagoya University, Nagoya, 464-8601 Japan.
authors.forename: Ayumu
authors.initials: A
authors.lastname: Inutsuka
authors.affiliation: Department of Neuroscience II, Research Institute of Environmental Medicine, Nagoya University, Nagoya, 464-8601 Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Yamashita
authors.affiliation: Department of Neuroscience II, Research Institute of Environmental Medicine, Nagoya University, Nagoya, 464-8601 Japan.
authors.forename: Srikanta
authors.initials: S
authors.lastname: Chowdhury
authors.affiliation: Saitama University Graduate School of Science and Engineering, 255 Shimo-Okubo, Sakura-ku, Saitama City, Saitama, 338-8570 Japan.|Saitama University Brain Science Institute, 255 Shimo-Okubo, Sakura-ku, Saitama City, Saitama, 338-8570 Japan.
authors.forename: Junichi
authors.initials: J
authors.lastname: Nakai
authors.affiliation: Saitama University Graduate School of Science and Engineering, 255 Shimo-Okubo, Sakura-ku, Saitama City, Saitama, 338-8570 Japan.|Saitama University Brain Science Institute, 255 Shimo-Okubo, Sakura-ku, Saitama City, Saitama, 338-8570 Japan.
authors.forename: Masamichi
authors.initials: M
authors.lastname: Ohkura
authors.affiliation: Department of Neuroscience II, Research Institute of Environmental Medicine, Nagoya University, Nagoya, 464-8601 Japan.
authors.forename: Toru
authors.initials: T
authors.lastname: Taguchi
authors.affiliation: Department of Neuroscience II, Research Institute of Environmental Medicine, Nagoya University, Nagoya, 464-8601 Japan.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Yamanaka
mesh_terms: D000700:Analgesics / Q000008:administration & dosage* / Q000494:pharmacology; D000818:Animals; D004195:Disease Models, Animal; D051379:Mice; D009474:Neurons / Q000502:physiology*; D059225:Nociception / Q000187:drug effects*; D000068797:Orexins / Q000378:metabolism*; D010783:Photometry; D014851:Wakefulness / Q000187:drug effects*
chemical_list: D000700:Analgesics; D000068797:Orexins