Caffeine increases light responsiveness of the mouse circadian pacemaker
- 5 September 2014
- journal article
- Published by Wiley in European Journal of Neuroscience
- Vol. 40 (10), 3504-3511
- https://doi.org/10.1111/ejn.12715
Abstract
Caffeine is the most commonly used psychoactive stimulant worldwide. It reduces sleep and sleepiness by blocking access to the adenosine receptor. The level of adenosine increases during sleep deprivation, and is thought to induce sleepiness and initiate sleep. Light-induced phase shifts of the rest-activity circadian rhythms are mediated by light-responsive neurons of the suprachiasmatic nucleus (SCN) of the hypothalamus, where the circadian clock of mammals resides. Previous studies have shown that sleep deprivation reduces circadian clock phase-shifting capacity and decreases SCN neuronal activity. In addition, application of adenosine agonists and antagonists mimics and blocks, respectively, the effect of sleep deprivation on light-induced phase shifts in behaviour, suggesting a role for adenosine. In the present study, we examined the role of sleep deprivation in and the effect of caffeine on light responsiveness of the SCN. We performed in vivo electrical activity recordings of the SCN in freely moving mice, and showed that the sustained response to light of SCN neuronal activity was attenuated after 6 h of sleep deprivation prior to light exposure. Subsequent intraperitoneal application of caffeine was able to restore the response to light. Finally, we performed behavioural recordings in constant conditions, and found enhanced period lengthening during chronic treatment with caffeine in drinking water in constant light conditions. The data suggest that increased homeostatic sleep pressure changes circadian pacemaker functioning by reducing SCN neuronal responsiveness to light. The electrophysiological and behavioural data together provide evidence that caffeine enhances clock sensitivity to light.Keywords
Funding Information
- Nederlandse Organisatie voor Wetenschappelijk Onderzoek (818.02.016)
This publication has 60 references indexed in Scilit:
- The acute effects of light on murine sleep during the dark phase: importance of melanopsin for maintenance of light‐induced sleepEuropean Journal of Neuroscience, 2013
- Ultraviolet Light Provides a Major Input to Non-Image-Forming Light Detection in MiceCurrent Biology, 2012
- Caffeine lengthens circadian rhythms in miceBiochemical and Biophysical Research Communications, 2011
- Multiple hypothalamic cell populations encoding distinct visual informationJournal Of Physiology-London, 2011
- Circadian Rhythms: Influences of Internal and External Factors on the Period Measured in Constant Conditions1Zeitschrift Fur Tierpsychologie, 2010
- Convergence of circadian and sleep regulatory mechanisms on hypocretin-1Neuroscience, 2004
- Light response of the neuronal firing activity in the suprachiasmatic nucleus of miceNeuroscience Letters, 2004
- Adenosine‐induced presynaptic inhibition of IPSCs and EPSCs in rat hypothalamic supraoptic nucleus neuronesJournal Of Physiology-London, 1999
- Circadian rhythm in adenosine A1 receptor of mouse cerebral cortexLife Sciences, 1991
- Inhibition of [3H] glutamate release from rat hippocam pal slices by L‐phenylisopropyladenosineActa Physiologica Scandinavica, 1985