Hibernation found to be neuroprotective
12 Sep 2011 by Evoluted New Media
Hibernation is an essential survival strategy for some animals, and scientists believe it might hold some promise for human survival too.
Hibernation is an essential survival strategy for some animals, and scientists believe it might hold some promise for human survival too. Hibernating animals have a reduced heart rate and blood flow – similar to a person in cardiac arrest – yet don’t suffer the brain damage that can occur in people. Scientists have successfully induced hibernation at will in arctic ground squirrels – a finding which may one day be applied to humans.
Researchers from the Institute of Arctic Biology devised an experiment in which non-hibernating arctic ground squirrels were given a substance that stimulated adenosine receptors in their brains to induce hibernation.
“When a squirrel begins to hibernate and when you feel drowsy it’s because adenosine molecules have attached themselves to receptors in your brain,” said lead author Tulasi Jinka.
These receptors can be regulated by caffeine, which is similar enough in structure to adenosine that it binds to receptors and stops or reverses drowsiness. Hibernating squirrels in the experiment were given a caffeine-like substance to wake them up.
Non-hibernating squirrels were tested three times during one year; once during the summer, again in early hibernation and a third time mid-way through the hibernation season. Torpor – a severely reduced metabolism and low oxygen consumption – was observed in all six woken during mid-hibernation, but only in two from the early hibernation group, and none in the summer.
“We showed for the first time that activation of the adenosine receptors is sufficient to induce torpor in arctic ground squirrels during their hibernation season,” said Jinka.
“Understanding the neuroprotective qualities of hibernating animals may lead to development of a drug or therapy to save people’s lives after a stroke or heart attack,” said Kelly Drew, senior author and UAF professor of chemistry and biochemistry.
The pair – who published their work in The Journal of Neuroscience – is expanding their research to rats, which more closely resemble the physiology of humans.
