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Parallel Measurement of Circadian Clock Gene Expression and Hormone Secretion in Human Primary Cell Cultures
Published on: November 11, 2016
Signals from the brainstem sleep/wake centers regulate behavioral timing via the circadian clock
Sabra M Abbott1, Jennifer M Arnold, Qing Chang
1Department of Molecular & Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.
Plos One
|August 17, 2013
Summary
Brainstem stimulation impacts the master circadian clock (SCN) by releasing neurotransmitters like acetylcholine and glutamate. This communication resets behavioral rhythms, revealing how vigilance influences sleep-wake cycles.
Area of Science:
- Neuroscience
- Chronobiology
- Sleep Science
Background:
- Sleep-wake cycles depend on vigilance and circadian systems.
- Connections between vigilance centers and the suprachiasmatic nucleus (SCN) are poorly understood.
- The SCN acts as the master circadian clock, regulating time-of-day signals.
Purpose of the Study:
- To investigate neurochemical communication from vigilance-regulating brain regions to the SCN.
- To determine the functional impact of this communication on circadian rhythms.
- To explore the role of neurotransmitters in integrating vigilance and circadian timing.
Main Methods:
- Discrete stimulation of pontine nuclei controlling vigilance state in mice.
- Analytical chemical measurements of microdialysates within the SCN.
- Assessment of behavioral circadian rhythm resetting following stimulation.
Main Results:
- Stimulation induced significant neurotransmitter release (acetylcholine, glutamate) within the SCN.
- SCN neurotransmitter level changes were correlated with resetting of behavioral circadian rhythms.
- The effects varied based on stimulus conditions and time-of-day.
Conclusions:
- Established neurochemical communication pathways from vigilance centers to the central circadian clock.
- Demonstrated behavioral consequences of this brainstem-SCN communication.
- Suggests a mechanism for dynamic integration of vigilance and circadian systems, potentially relevant to sleep disorders.
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