Related Experiment Videos
Adenosine and caffeine modulate circadian rhythms in the Syrian hamster
M C Antle1, N M Steen, R E Mistlberger
1Department of Psychology, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada.
Neuroreport
|October 6, 2001
Summary
Adenosine A1 agonists mimic sleep deprivation effects on circadian rhythms. Caffeine blocks these shifts, suggesting adenosine
Area of Science:
- Neuroscience
- Chronobiology
- Sleep Research
Background:
- Extracellular adenosine levels increase in specific brain regions during sleep deprivation.
- Sleep deprivation and adenosine A1 receptor agonists can inhibit circadian rhythm phase shifts induced by light at night.
- Sleep deprivation during the day (active sleep period) can shift circadian phase.
Purpose of the Study:
- To investigate if the adenosine A1 agonist N-cyclohexyladenosine (N-CHA) mimics the phase-shifting effects of sleep deprivation on circadian rhythms.
- To determine the role of adenosine in resetting the circadian clock through behavioral state manipulation.
Main Methods:
- Administration of N-CHA (intraperitoneal or intracerebral) during the mid-sleep period in Syrian hamsters.
- Administration of caffeine, an adenosine antagonist, during the mid-sleep period.
- Assessment of circadian phase shifts following these interventions and a 3-hour sleep deprivation procedure (running in a novel wheel).
Main Results:
- N-CHA administration induced dose-dependent phase shifts similar to those caused by 3 hours of sleep deprivation.
- Systemic caffeine administration induced arousal but no phase shifts.
- Caffeine dose-dependently attenuated the phase-shifting effects of sleep deprivation.
Conclusions:
- Adenosine A1 receptor activation can mimic the phase-shifting effects of sleep deprivation on circadian rhythms.
- Adenosine likely plays a role in the resetting of circadian clocks by modulating behavioral states.
- These findings suggest a link between sleep, adenosine signaling, and circadian clock regulation.