Pontomesencephalic tegmental cholinergic neurons were destroyed in cats by local injections of kainic acid in order to assess the role of these neurons in sleep-wakefulness states and in the defining variables of these states: EEG (electroencephalographic) and EMG (electromyographic) amplitude, PGO (ponto-geniculo-occipital) spike rate, REMs (rapid eye movements) and (OBS) olfactory bulb spindles. Loss of cholinergic innervation to forebrain and brainstem structures was also assessed by histochemistry. Histological and histochemical analysis of the brains after the lesion showed a major destruction of the pontomesencephalic cholinergic neurons and a major loss of innervation to thalamic nuclei and brainstem regions, including the reticular formation. Whereas the states of waking and slow wave sleep were relatively unaffected, paradoxical sleep (PS) was reduced or eliminated immediately following the lesions. Two to three weeks later, incipient PS-like episodes returned with a reduced PGO spike rate and REMs, and an elevated EMG amplitude, marking the loss of muscle atonia. Such results suggest pontomesencephalic cholinergic neurons and their projections to thalamic and brainstem regions are important for the expression of PS and its defining variables.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.75890 |
| Date | January 1988 |
| Creators | Webster, Harry, 1947- |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Doctor of Philosophy (Department of Psychology.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 000913001, proquestno: AAINL52208, Theses scanned by UMI/ProQuest. |
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