title: Involvement of the orexin system in adrenal sympathetic regulation.
abstract: Orexin (hypocretin) is a neuropeptide secreted from hypothalamic neurons that is known to be activated during motivated behaviors and active waking. Presently, our knowledge of orexin is mainly limited to the central nervous system, and the involvement of the orexin system in peripheral tissues has received little attention. In the present study, we analyzed the existence of the orexin system in the adrenal medulla, which is part of the sympathetic nervous system. Orexin and its receptors are expressed in the bovine adrenal medulla. Orexins stimulated intracellular calcium changes and epinephrine release from cultured bovine adrenal medullary cells. Applied orexin decreased expression of prepro-orexin, orexin receptor-1 and orexin receptor-2, suggesting negative feedback regulation in the adrenal gland. Our results indicate involvement of the orexin system in the sympathetic regulation of the adrenal medulla.
authors: Department of Pharmacology, Graduate School of Medicine, University of Miyazaki, Miyazaki, Japan.
authors: Takayuki
authors: T
authors: Nemoto
authors: Fumiyo
authors: F
authors: Toyoshima-Aoyama
authors: Yuto
authors: Y
authors: Ueda
authors: Takayoshi
authors: T
authors: Ohba
authors: Toshihiko
authors: T
authors: Yanagita
authors: Hiroyuki
authors: H
authors: Watanabe
authors: Tetsuro
authors: T
authors: Shirasaka
authors: Isao
authors: I
authors: Tsuneyoshi
authors: Yasushi
authors: Y
authors: Ishida
authors: Kazuyoshi
authors: K
authors: Hirota
authors: Akira
authors: A
authors: Sawaguchi
authors: Manabu
authors: M
authors: Murakami
mesh_terms: D000313:Adrenal Medulla / Q000378:metabolism*; D000818:Animals; D002118:Calcium / Q000378:metabolism; D002417:Cattle; D002478:Cells, Cultured; D019439:Chromaffin Cells / Q000378:metabolism*; D004837:Epinephrine / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism*; D050778:NFATC Transcription Factors / Q000378:metabolism; D009479:Neuropeptides / Q000235:genetics / Q000378:metabolism*; D064446:Orexin Receptors / Q000235:genetics / Q000378:metabolism*; D000068797:Orexins; D012333:RNA, Messenger / Q000378:metabolism
chemical_list: D047908:Intracellular Signaling Peptides and Proteins; D050778:NFATC Transcription Factors; D009479:Neuropeptides; D064446:Orexin Receptors; D000068797:Orexins; D012333:RNA, Messenger; D002118:Calcium; D004837:Epinephrine