title: Orexin-B antagonized respiratory depression induced by sevoflurane, propofol, and remifentanil in isolated brainstem-spinal cords of neonatal rats.
abstract: Orexins (hypocretins) play a crucial role in arousal, feeding, and endocrine function. We previously reported that orexin-B activated respiratory neurons in the isolated brainstem-spinal cords of neonatal rats. We herein determined whether orexin-B antagonized respiratory depression induced by sevoflurane, propofol, or remifentanil. We recorded C4 nerve bursts as an index of inspiratory activity in a brainstem-spinal cord preparation. The preparation was superfused with a solution equilibrated with 3% sevoflurane alone for 10 min and the superfusate was then switched to a solution containing sevoflurane plus orexin-B. Sevoflurane decreased the C4 burst rate and the integrated C4 amplitude. The C4 burst rate and amplitude were reversed by 0.5 μM orexin-B, but not by 0.1 μM orexin-B. The decrease induced in the C4 burst rate by 10 μM propofol or 0.01 μM remifentanil was significantly antagonized by 0.1 μM orexin-B. Respiratory depression induced by a higher concentration (0.1 μM) of remifentanil was not restored by 0.1 μM orexin-B. These results demonstrated that orexin-B antagonized respiratory depression induced by sevoflurane, propofol, or remifentanil.
authors.affiliation: Department of Anesthesiology, Kanagawa Dental University, Yokosuka City 238-8580, Japan.
authors.forename: Nobuo
authors.initials: N
authors.lastname: Umezawa
authors.affiliation: Department of Anesthesiology, Kanagawa Dental University, Yokosuka City 238-8580, Japan.
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Arisaka
authors.affiliation: Department of Anesthesiology, Kanagawa Dental University, Yokosuka City 238-8580, Japan.
authors.forename: Shigeki
authors.initials: S
authors.lastname: Sakuraba
authors.affiliation: Department of Anesthesiology, Kanagawa Dental University, Yokosuka City 238-8580, Japan.
authors.forename: Takeo
authors.initials: T
authors.lastname: Sugita
authors.affiliation: Department of Anesthesiology, Kanagawa Dental University, Yokosuka City 238-8580, Japan.
authors.forename: Akiko
authors.initials: A
authors.lastname: Matsumoto
authors.affiliation: Department of Physiology, Faculty of Health Sciences, Uekusa Gakuen University, Chiba City 264-0007, Japan; Center for Medical Sciences, Ibaraki Prefectural University of Health Sciences, Ibaraki-ken 300-0394, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Kaku
authors.affiliation: Department of Anesthesiology, Kanagawa Dental University, Yokosuka City 238-8580, Japan.
authors.forename: Kazu-ichi
authors.initials: K
authors.lastname: Yoshida
authors.affiliation: Department of Physiology, Faculty of Health Sciences, Uekusa Gakuen University, Chiba City 264-0007, Japan. Electronic address: s-kuwana@uekusa.ac.jp.
authors.forename: Shun-ichi
authors.initials: S
authors.lastname: Kuwana
mesh_terms: D000777:Anesthetics / Q000494:pharmacology*; D000818:Animals; D000831:Animals, Newborn; D001933:Brain Stem / Q000187:drug effects*; D004195:Disease Models, Animal; D047908:Intracellular Signaling Peptides and Proteins / Q000494:pharmacology*; D008738:Methyl Ethers / Q000494:pharmacology; D009479:Neuropeptides / Q000494:pharmacology*; D000068797:Orexins; D010880:Piperidines / Q000494:pharmacology; D015742:Propofol / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D000077208:Remifentanil; D012131:Respiratory Insufficiency / Q000139:chemically induced* / Q000517:prevention & control; D000077149:Sevoflurane; D013116:Spinal Cord / Q000187:drug effects*
chemical_list: D000777:Anesthetics; D047908:Intracellular Signaling Peptides and Proteins; D008738:Methyl Ethers; D009479:Neuropeptides; D000068797:Orexins; D010880:Piperidines; D000077149:Sevoflurane; D000077208:Remifentanil; D015742:Propofol
keywords: Anesthetics; Isolated brainstem; Neontal rat; Orexin; Respiration