Pontine Brainstem Research Articles

Sleep cycle control and cholinergic mechanisms: Differential effects of carbachol injections at pontine brain stem sites

Muscular atonia and cortical desynchronization, two signs of desynchronized sleep, can be enhanced or suppressed by direct injection of carbachol into the pontine brain stem of cats. The positive effects are graded, being maximal in the gigantocellular tegmental field and less marked in adjacent nuclei. These positive effects are dose-dependent. Suppressive effects of carbachol are maximal in the region of the locus coeruleus and are dose-dependent but do not exceed those of the vehicle alone. The results support the hypothesis that cholinergic mechanisms of the pontine tegmentum are involved in desynchronized sleep generation.

Discharge patterns of cat pontine brain stem neurons during desynchronized sleep.

1. Discharge pattern has been characterized by autocorrelation analysis of stationary portions of extracellularly recorded discharge trains of cat pontine brain stem neurons during spontaneously occurring desynchronized sleep episodes. 2. Neurons localized to the area implicated in control of the desynchronized phase of sleep, the gigantocellular tegmental field (FTG), show the most phasic or clustered discharge pattern, as evinced by initial peaks in the autocorrelations. At the peak, the FTG population average discharge probability is 3 times that expected had the discharges been evenly distributed over time. The initial peak extends beyond a lag of 3 s, indicating runs of clustered discharge extending beyond this duration. Neurons in other reticular tegmental fields, the tegmental reticular nucleus and pontine gray, show a more sustained or tonic discharge pattern. 3. Discharge patterns of a given cell are consistent from one desynchronized sleep episode to the next; units with phasic discharge patterns remain phasic, and tonic patterns remain tonic. 4. There is a three-way correlation among FTG units recorded at sites with many giant cells, units with high discharge rate increases on transition to desynchronized sleep, and units with a markedly phasic discharge pattern. This implicates the giant cells as the source of both the distinctive discharge rate and pattern changes of neurons during desynchronized sleep. 5. Stereotyped, regular discharge patterns are not characteristic of FTG or other units, suggesting they are not pacemakers and that endogenous activation of pacemaker cells is unlikely to be a mechanism for generation of the marked discharge rate increases on transition to desynchronized sleep that are found in FTG units. The irregular, clustered discharge pattern of FTG is more compatible with generation of discharge rate increases through interaction with other cells. The markedly phasic discharge of FTG units is also consistent with a driving role in generation of the phasic electrophysiologic events of desynchronized sleep.

Time course of discharge rate changes by cat pontine brain stem neurons during sleep cycle.

Time course of discharge rate changes by cat pontine brain stem neurons during sleep cycle.J A Hobson, R W McCarley, R Freedman, and R T PivikJ A Hobson, R W McCarley, R Freedman, and R T PivikPublished Online:01 Nov 1974https://doi.org/10.1152/jn.1974.37.6.1297MoreSectionsPDF (2 MB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInWeChat Previous Back to Top Next Download PDF FiguresReferencesRelatedInformation Cited ByImmune and Neuroprotective Effects of Physical Activity on the Brain in Depression26 July 2018 | Frontiers in Neuroscience, Vol. 12Firing of neurons in the preoptic/anterior hypothalamic areas in rat: its possible involvement in slow wave sleep and paradoxical sleepNeuroscience Research, Vol. 19, No. 1The effects of changing state on elicited ponto-geniculo-occipital (PGO) wavesElectroencephalography and Clinical Neurophysiology, Vol. 79, No. 5Neuronal firing in the pallidal region: firing patterns during sleep-wakefulness cycle in catsElectroencephalography and Clinical Neurophysiology, Vol. 67, No. 2Neuronal excitability control in health and disease: A neurophysiological comparison of REM sleep and epilepsyProgress in Neurobiology, Vol. 25, No. 2Site-specific enhancement and suppression of desynchronized sleep signs following cholinergic stimulation of three brainstem regionsBrain Research, Vol. 306, No. 1-2Brainstem control of the events of rem sleepProgress in Neurobiology, Vol. 22, No. 3Firing rates and patterns of midbrain reticular neurons during steady and transitional states of the sleep-waking cycle3 September 2013 | Experimental Brain Research, Vol. 46, No. 1Elimination of paradoxical sleep by lesions of the pontine gigantocellular tegmental field in the catNeuroscience Letters, Vol. 13, No. 3Duration of paradoxical sleep episodes. A quantitative and pattern analysis of reticular multi-unit activity in the catElectroencephalography and Clinical Neurophysiology, Vol. 43, No. 2Eye movement-associated discharge in brain stem neurons during desynchronized sleepBrain Research, Vol. 121, No. 1Processing of sensory informationProgress in Neurobiology, Vol. 9, No. 1-2Oscillatory activity of pontine neurons related to the regular occurence of REM bursts in the decerebrate catBrain Research, Vol. 116, No. 1Central control of posture: reciprocal discharge by two pontine neuronal groups leading to suppression of decerebrate rigidityBrain Research, Vol. 116, No. 1Visual cortical neurons influenced by the oculomotor input: Characterization of their receptive field propertiesBrain Research, Vol. 113, No. 2Brain stem neurons that fire selectively to a conditioned stimulus for shockBrain Research, Vol. 103, No. 2 More from this issue > Volume 37Issue 6November 1974Pages 1297-309 https://doi.org/10.1152/jn.1974.37.6.1297PubMed4436702History Published online 1 November 1974 Published in print 1 November 1974 Metrics

Localization with pontamine sky blue of neurones in the brainstem responding to microiontophoretically applied compounds

A development of the technique of marking electrode tip positions with Pontamine Sky Blue is described. The locations of a number of neurones in the medullary and pontine brainstem of the rat which were found to be sensitive to microiontophoretically applied noradrenaline, 5-hydroxytryptamine or morphine are presented, and the difficulties of interpretation of the results discussed.

Selective firing by cat pontine brain stem neurons in desynchronized sleep.

Selective firing by cat pontine brain stem neurons in desynchronized sleep.

Olivo-cochlear inhibition during physostigmine-induced activity in the pontine reticular formation in the decerebrate cat

The physiological role of the olivo-cochlear pathway has been questioned recently because this pathway has never been shown to be operative under natural conditions. In this study, cochlear potentials were recorded differentially between a wire electrode placed on the round window and an indifferent electrode attached to the nuchal muscles in decerebrate, decerebellate cats. Physostigmine was used to induce bout of rapid eye movement (REM) sleep. REM bouts were verified by recording burst activity in the brain stem pontine reticular formation and the inhibition of lumbar monosynaptic reflexes. Intravenous physostigmine increased the inhibition of N 1 caused by direct electrical stimulation of the crossed olivo-cochlear bundle in the absence of REM. Olivo-cochlear system inhibition was also recruited during physostigmine-induced REM sleep. It is concluded that the brain stem reticular formation can activate the olivo-cochlear bundle and can thereby produce inhibition in the cochlea.

A first-order synaptic relay for taste fibers in the pontine brain stem of the cat

Summary Microelectrode recordings were used to locate taste responsive neurons in a recently discovered area of termination of facial nerve afferents in the pontine brain stem of the cat. The neurons were activated by electrical stimulation of the chorda tympani nerve, followed by stimulation of the tongue with standard taste of solutions. Electrolytic lesions were made to mark the depth of active sites and electrode penetrations were reconstructed from frozen serial sections. The taste neurons were found in a group of cells lying outside and dorsomedial to the main body of the principal sensory trigeminal nucleus. The small size of the taste responsive area and its relationship to typical trigeminal responses lend weight to the existence of a morphologically distinct nucleus intertrigeminails reported elsewhere. The report of an uncrossed dorsal trigeminal tract linking this area to the thalamus would explain the ipsilateral taste projection found in the thalamus of cat and monkey. The contralateral taste projection in the rat would be consistent with the absence of a pontine termination for the facial afferents in that species. The existence of a taste are in the bulbar solitary nucleus of the cat was confirmed and its possible role in taste function is discussed.