Faculty Opinions recommendation of Cerebral O2 metabolism and cerebral blood flow in humans during deep and rapid-eye-movement sleep.

It could be expected that the various stages of sleep were reflected in variation of the overall level of cerebral activity and thereby in the magnitude of cerebral metabolic rate of oxygen (CMRO2) and cerebral blood flow (CBF). The elusive nature of sleep imposes major methodological restrictions on examination of this question. We have now measured CBF and CMRO2 in young healthy volunteers using the Kety-Schmidt technique with 133Xe as the inert gas. Measurements were performed during wakefulness, deep sleep (stage 3/4), and rapid-eye-movement (REM) sleep as verified by standard polysomnography. Contrary to the only previous study in humans, which reported an insignificant 3% reduction in CMRO2 during sleep, we found a deep-sleep-associated statistically highly significant 25% decrease in CMRO2, a magnitude of depression according with studies of glucose uptake and reaching levels otherwise associated with light anesthesia. During REM sleep (dream sleep) CMRO2 was practically the same as in the awake state. Changes in CBF paralleled changes in CMRO2 during both deep and REM sleep.

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Patterned cardiovascular responses to sleep and nonrespiratory arousals in a porcine model

Journal of Applied Physiology ◽

10.1152/jappl.1998.85.4.1285 ◽

1998 ◽

Vol 85 (4) ◽

pp. 1285-1291 ◽

Cited By ~ 7

Author(s):

Sandrine H. Launois ◽

Joseph H. Abraham ◽

J. Woodrow Weiss ◽

Debra A. Kirby

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Blood Flow ◽

Eye Movement ◽

Arterial Blood Pressure ◽

Vascular Resistance ◽

Mean Arterial Blood Pressure ◽

Rapid Eye Movement ◽

Rapid Eye Movement Sleep ◽

Arterial Blood

Patients with obstructive sleep apnea experience marked cardiovascular changes with apnea termination. Based on this observation, we hypothesized that sudden sleep disruption is accompanied by a specific, patterned hemodynamic response, similar to the cardiovascular defense reaction. To test this hypothesis, we recorded mean arterial blood pressure, heart rate, iliac blood flow and vascular resistance, and renal blood flow and vascular resistance in five pigs instrumented with chronic sleep electrodes. Cardiovascular parameters were recorded during quiet wakefulness, during non-rapid-eye-movement and rapid-eye-movement sleep, and during spontaneous and induced arousals. Iliac vasodilation (iliac vascular resistance decreased by −29.6 ± 4.1% of baseline) associated with renal vasoconstriction (renal vascular resistance increased by 10.3 ± 4.0%), tachycardia (heart rate increase: +23.8 ± 3.1%), and minimal changes in mean arterial blood pressure were the most common pattern of arousal response, but other hemodynamic patterns were observed. Similar findings were obtained in rapid-eye-movement sleep and for acoustic and tactile arousals. In conclusion, spontaneous and induced arousals from sleep may be associated with simultaneous visceral vasoconstriction and hindlimb vasodilation, but the response is variable.

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Longitudinal study of regional cerebral blood flow in elderly patients with idiopathic rapid eye movement sleep behavior disorder

Geriatrics and Gerontology International ◽

10.1111/ggi.12068 ◽

2013 ◽

Vol 14 (1) ◽

pp. 115-120 ◽

Cited By ~ 15

Author(s):

Hirofumi Sakurai ◽

Haruo Hanyu ◽

Yuichi Inoue ◽

Hidekazu Kanetaka ◽

Masaki Nakamura ◽

...

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Longitudinal Study ◽

Elderly Patients ◽

Eye Movement ◽

Regional Cerebral Blood Flow ◽

Behavior Disorder ◽

Rapid Eye Movement Sleep ◽

Regional Cerebral Blood ◽

Sleep Behavior

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Linkage between brain blood flow and respiratory drive during rapid-eye-movement sleep

Journal of Applied Physiology ◽

10.1152/jappl.1988.64.4.1457 ◽

1988 ◽

Vol 64 (4) ◽

pp. 1457-1465 ◽

Cited By ~ 14

Author(s):

R. A. Parisi ◽

J. A. Neubauer ◽

M. M. Frank ◽

T. V. Santiago ◽

N. H. Edelman

Keyword(s):

Blood Flow ◽

Eye Movement ◽

Rem Sleep ◽

Emg Activity ◽

Respiratory Drive ◽

Brain Blood Flow ◽

Rapid Eye Movement ◽

Rapid Eye Movement Sleep ◽

Inspiratory Time ◽

Phasic Activity

The correlation between brain blood flow (BBF) and respiratory neuromotor output, as reflected by diaphragmatic electromyogram (EMG) activity (EMGdi), was studied during wakefulness, rapid-eye-movement (REM) sleep, and non-REM sleep (NREM). Compared with the awake state, mean BBF increased by 4.7% during NREM and by 32.6% during REM (P less than 0.001). Also, surges of BBF during REM occurred during periods of intense phasic activity. EMGdi [peak and peak/inspiratory time (TI)] was highly variable within REM periods but fluctuated as a reciprocal function of simultaneously measured BBf (r = -0.49, P less than 0.001). Furthermore, mean EMGdipeak decreased from NREM to REM in a manner reciprocally related to the corresponding change in BBF (r = -0.77, P = 0.015). These findings suggest that a component of the reduction of respiratory neuromotor output during REM is attributable to increased BBF with consequent relative hypocapnia in the central chemoreceptor environment.

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