Systemic hemodynamic changes raising brain temperature in REM sleep.

Pier Luigi Parmeggiani; Adele Azzaroni; Marcella Calasso

doi:10.1016/s0006-8993(02)02591-x

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PubMed · 12020875

Systemic hemodynamic changes raising brain temperature in REM sleep.

Pier Luigi Parmeggiani·Adele Azzaroni·Marcella Calasso

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Abstract

The present research studied the mechanisms underlying the increase in brain temperature during REM sleep in the unrestrained rabbit carrying chronically implanted electrodes, thermistors and common carotid artery occluders. During the ultradian wake-sleep cycle at constant ambient temperature (25+/-2 degrees C), we recorded: (i) the ear pinna temperature as an indirect indicator of blood flow affecting heat loss from the systemic heat exchangers of the head, (ii) the temperature of the pons and hypothalamus as indirect indicators of the temperature of vertebral artery blood (systemic cooling only) and carotid artery blood (both systemic and selective cooling), respectively, and (iii) the changes induced in these temperatures by short-lasting bilateral common carotid artery occlusion. The results show that during REM sleep both systemic and selective brain cooling are depressed by a spontaneous decrease in the common carotid artery blood flow and the associated autoregulatory increase in the vertebral artery share of the cerebral blood supply.

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Activity Cycles Animals Body Temperature Brain Carotid Arteries Cerebrovascular Circulation Electrodes, Implanted Electroencephalography Electromyography Hemodynamics Hypothalamus Ischemic Attack, Transient Pons Rabbits Sleep, REM Journal Article Research Support, Non-U.S. Gov't

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Pier Luigi Parmeggiani, Adele Azzaroni, Marcella Calasso. 2002-06-14. Systemic hemodynamic changes raising brain temperature in REM sleep.. https://doi.org/10.1016/s0006-8993(02)02591-x

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