biological clock stimulates thirst in the hours before sleep, according
to a study published in the journal Nature by researchers from the
Research Institute of the McGill University Health Centre (RI-MUHC).
The finding – along with the discovery of the molecular process
behind it – provides the first insight into how the clock regulates a
physiological function. And while the research was conducted in mice,
“the findings could point the way toward drugs that target receptors
implicated in problems that people experience from shift work or jet
lag,” says the study’s senior author, Charles Bourque, a professor in
McGill’s Department of Neurology and scientist at the Brain Repair and Integrative Neuroscience Program at the (RI-MUHC).
Scientists knew that rodents show a surge in water intake during the
last two hours before sleep. The study by Bourque’s group revealed that
this behavior is not motivated by any physiological reason, such as
dehydration. So if they don’t need to drink water, why do they?
The team of researchers, which included lead author and Ph.D. student
Claire Gizowski, found that restricting the access of mice to water
during the surge period resulted in significant dehydration towards the
end of the sleep cycle. So the increase in water intake before sleep is a
preemptive strike that guards against dehydration and serves to keep
the animal healthy and properly hydrated.
It’s well established
that the brain harbors a hydration sensor with thirst neurons in that
sensor organ. So they wondered if the SCN (suprachiasmatic nuclei), the
brain region that regulates circadian cycles – a.k.a. the biological
clock – could be communicating with the thirst neurons. Neurosciencenews
image is for illustrative purposes only.
Concept: Your arms are wrapped around me as we lay in bed. We talk and make jokes and call each other empty insults to make each other laugh. You press kisses to my cheek every so often and I can feel your fingers tracing my side. We’re finally together and everything feels right and happy.