title: Eye movements and abducens motoneuron behavior after cholinergic activation of the nucleus reticularis pontis caudalis.
abstract: OBJECTIVE
  the aim of this work was to characterize eye movements and abducens (ABD) motoneuron behavior after cholinergic activation of the nucleus reticularis pontis caudalis (NRPC).
  
  
  METHODS
  six female adult cats were prepared for chronic recording of eye movements (using the scleral search-coil technique), electroencephalography, electromyography, ponto-geniculo-occipital (PGO) waves in the lateral geniculate nucleus, and ABD motoneuron activities after microinjections of the cholinergic agonist carbachol into the NRPC.
  
  
  RESULTS
  unilateral microinjections of carbachol in the NRPC induced tonic and phasic phenomena in the oculomotor system. Tonic effects consisted of ipsiversive rotation to the injected side, convergence, and downward rotation of the eyes. Phasic effects consisted of bursts of rhythmic rapid eye movements directed contralaterally to the injected side along with PGO-like waves in the lateral geniculate and ABD nuclei. Although tonic effects were dependent on the level of drowsiness, phasic effects were always present and appeared along with normal saccades when the animal was vigilant. ABD motoneurons showed phasic activities associated with ABD PGO-like waves during bursts of rapid eye movements, and tonic and phasic activities related to eye position and velocity during alertness.
  
  
  CONCLUSIONS
  the cholinergic activation of the NRPC induces oculomotor phenomena that are somewhat similar to those described during REM sleep. A precise comparison of the dynamics and timing of the eye movements further suggests that a temporal organization of both NRPCs is needed to reproduce the complexity of the oculomotor behavior during REM sleep.
authors.affiliation: División de Neurosciencias, Universidad Pablo de Olavide, Sevilla, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Márquez-Ruiz
authors.forename: Miguel
authors.initials: M
authors.lastname: Escudero
mesh_terms: D000010:Abducens Nerve / Q000187:drug effects*; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D002217:Carbachol / Q000494:pharmacology; D002415:Cats; D018679:Cholinergic Agonists / Q000494:pharmacology*; D004569:Electroencephalography / Q000187:drug effects / Q000379:methods; D004576:Electromyography / Q000187:drug effects / Q000379:methods; D005133:Eye Movements / Q000187:drug effects*; D005260:Female; D009046:Motor Neurons / Q000187:drug effects*; D009434:Neural Pathways / Q000187:drug effects; D009801:Oculomotor Muscles / Q000187:drug effects / Q000294:innervation; D009802:Oculomotor Nerve / Q000187:drug effects; D011149:Pons / Q000187:drug effects*; D012154:Reticular Formation / Q000187:drug effects*; D014851:Wakefulness / Q000187:drug effects
chemical_list: D018679:Cholinergic Agonists; D002217:Carbachol