Interleukin-1beta has a role in cerebral cortical state-dependent electroencephalographic slow-wave activity.
OBJECTIVE
To investigate the hypothesis that interleukin (IL)-1beta is involved in mediating localized electroencephalogram synchronization.


METHODS
We evaluated bilateral cortical electroencephalograms after unilateral local application of IL-1beta onto the somatosensory cortex of rats. Furthermore, we investigated the effects of unilateral application of an IL-1beta inhibitor, the IL-1 soluble receptor, on spontaneous sleep and sleep rebound after sleep deprivation.


METHODS
University research laboratory.


METHODS
N/A.


METHODS
Rats.


RESULTS
Neither dose of IL-1beta or the IL-1 soluble receptor affected the duration of non-rapid eye movement sleep or rapid eye movement sleep. Unilateral application of IL-1beta induced state- and frequency-dependent electroencephalogram asymmetries. During non-rapid eye movement sleep, but not during other states, electroencephalographic slow-wave activity was greater on the side that received IL-1beta (10- and 50-ng doses). Electroencephalographic power in the higher frequencies was not affected by IL-1beta in any state. Unilateral application of the IL-1 soluble receptor (0.1, 1.0 and 5.0 microg) had no effect on the spontaneous sleep electroencephalogram. In contrast, unilateral application of the IL-1 soluble receptor (5.0 microg) attenuated sleep deprivation-enhanced electroencephalographic slow-wave power ipsilaterally during non-rapid eye movement sleep.


CONCLUSIONS
Results suggest that IL-1beta can induce state-dependent localized increases of electroencephalographic delta wave power, suggesting an enhancement of sleep intensity within the cortex.
Yasuda
Tadanobu
T
Department of Veterinary and Comparative Anatomy, Pharmacology and Physiology, Washington State University, Pullman, Washington 99164-6520, USA.
Yoshida
Hitoshi
H
Garcia-Garcia
Fabio
F
Kay
Daniel
D
Krueger
James M
JM
D000818:Animals; D002540:Cerebral Cortex / Q000378:metabolism* / Q000503:physiopathology*; D004569:Electroencephalography; D004576:Electromyography; D007839:Functional Laterality / Q000502:physiology; D007375:Interleukin-1 / Q000378:metabolism / Q000502:physiology*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012890:Sleep / Q000502:physiology*; D012894:Sleep Stages / Q000502:physiology; D012895:Sleep, REM / Q000502:physiology; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
D007375:Interleukin-1; D014409:Tumor Necrosis Factor-alpha