Monosynaptic inhibition of phrenic motoneurons: a long descending projection from Bötzinger neurons.
Synaptic connections between medullary expiratory neurons and phrenic motoneurons were studied in anesthetized cats using spike-triggered averaging of synaptic noise in phrenic motoneurons. Monosynaptic inhibition of phrenic motoneurons originating from the rostral medullary expiratory neurons of the Bötzinger complex was revealed. Neither mono- nor disynaptic inhibition from expiratory neurons of the nucleus retroambigualis was found. It was concluded that Bötzinger complex expiratory neurons make long descending inhibitory connections with phrenic motoneurons: the expiratory neurons of the nucleus retroambigualis do not appear to make synaptic connections with phrenic motoneurons.
D000818:Animals; D002415:Cats; D004525:Efferent Pathways / Q000502:physiology; D008526:Medulla Oblongata / Q000166:cytology / Q000502:physiology*; D009046:Motor Neurons / Q000502:physiology*; D009433:Neural Inhibition; D009474:Neurons / Q000502:physiology; D010791:Phrenic Nerve / Q000502:physiology*; D012137:Respiratory System / Q000294:innervation*; D013569:Synapses / Q000502:physiology*; D009435:Synaptic Transmission