Noradrenergic modulation of airway-related muscle activity across the sleep-wake cycle.
Published: 2006
Language: eng
Number of pages: 118
ISBN-13: 9780494211632
Description: Skeletal muscle tone is potently suppressed during natural sleep. Understanding the physiological mechanisms that regulate muscle activity during sleep is important as dysregulation of these processes underlies a number of major sleep disorders including the potentially lethal, obstructive sleep apnea (OSA). The neurophysiological mechanisms that regulate sleep-related changes in muscle activity are currently unclear. It is hypothesized that withdrawal of excitatory, noradrenergic inputs onto motoneurons reduces muscle tone during sleep. Accordingly, using the microdialysis technique, this study investigated the role of the noradrenergic system in regulating trigeminal motoneuron (TMN) excitability and hence airway-related masseter muscle (MASS) activation across the sleep wake cycle. Results provide evidence for the presence of a noradrenergic drive to TMNs that activates basal MASS activity during wakefulness, but not during NREM or REM sleep. Consistent with this finding, sleep related decreases in MASS activity were counteracted by the addition of noradrenergic inputs back onto TMNs.
Notes: Source: Masters Abstracts International, Volume: 45-03, page: 1401.

Thesis (M.Sc.)--University of Toronto, 2006.

Electronic version licensed for access by U. of T. users.

ROBARTS MICROTEXT copy on microfiche.