Serotonergic cells in nucleus raphe pallidus provide tonic drive to posterior cricoarytenoid motoneurons via 5-hydroxytryptamine2 receptors in cats.
Microinjection of serotonin and 5-hydroxytryptamine2 (5-HT2) agonist 1-(2,5-dimethoxy-4-methylphenyl)-2-aminopropane (DOM) in nucleus ambiguus caused excitation of posterior cricoarytenoid (PCA) muscles of the larynx in anesthetized, spontaneously breathing cats. Intravenous administration of 5-HT2 antagonist ketanserin produced complete block of excitatory effect of DOM injection. Electrical stimulation of nucleus raphe pallidus caused excitation of PCA activity, that was blocked by pretreatment of ketanserin. These results indicate that serotonergic cells in the raphe pallidus provide tonic drive to medullary PCA motoneurons through 5-HT2 receptors.
Arita
H
H
Department of Physiology, Toho University School of Medicine, Tokyo, Japan.
Ichikawa
K
K
Sakamoto
M
M
D004290:DOM 2,5-Dimethoxy-4-Methylamphetamine / Q000494:pharmacology; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin / Q000494:pharmacology; D000402:Airway Obstruction / Q000503:physiopathology; D000818:Animals; D002415:Cats; D004558:Electric Stimulation; D007650:Ketanserin / Q000494:pharmacology; D007821:Laryngeal Muscles / Q000166:cytology*; D008845:Microinjections; D009046:Motor Neurons / Q000502:physiology*; D011903:Raphe Nuclei / Q000166:cytology / Q000502:physiology*; D011985:Receptors, Serotonin / Q000502:physiology*; D012701:Serotonin / Q000502:physiology*; D012702:Serotonin Antagonists / Q000494:pharmacology; D017366:Serotonin Receptor Agonists / Q000494:pharmacology; D012895:Sleep, REM / Q000502:physiology
D011985:Receptors, Serotonin; D012702:Serotonin Antagonists; D017366:Serotonin Receptor Agonists; D004290:DOM 2,5-Dimethoxy-4-Methylamphetamine; D012701:Serotonin; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D007650:Ketanserin