title: Temporal patterns of trigeminal respiratory activity in rat brainstem-spinal cord in vitro.
abstract: Respiratory activity in trigeminal (V) motoneurons was studied in rhythmically active en bloc brainstem-spinal cord preparations isolated from neonatal rats (P0-P3). In the majority of preparations (83%), the temporal pattern of V activity consisted of spontaneous inspiratory phasic discharge with onset delayed or coincident with onset of phrenic motoneuron discharge. Blockade of alpha-2 noradrenergic receptor activation shifted onset of V respiratory discharges earlier than phrenic discharges, while elevation of extracellular potassium concentration or blockade of GABAergic and glycinergic inhibitory synaptic transmission had little effect on temporary pattern of V respiratory discharges. We conclude V motoneurons in the in vitro preparation generate respiratory activity during inspiratory phase, and their temporal patterns are modulated by inhibitory noradrenergic synaptic transmission.
authors.affiliation: The First Department of Oral and Maxillofacial Surgery, Osaka University Faculty of Dentistry, Suita, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Koizumi
authors.forename: K
authors.initials: K
authors.lastname: Nomura
authors.forename: K
authors.initials: K
authors.lastname: Ishihama
authors.forename: M
authors.initials: M
authors.lastname: Kogo
authors.forename: T
authors.initials: T
authors.lastname: Matsuya
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001933:Brain Stem / Q000502:physiology*; D066298:In Vitro Techniques; D009638:Norepinephrine / Q000502:physiology; D010791:Phrenic Nerve / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012119:Respiration; D013116:Spinal Cord / Q000502:physiology*; D009435:Synaptic Transmission / Q000502:physiology; D014276:Trigeminal Nerve / Q000502:physiology*
chemical_list: D009638:Norepinephrine