Understanding ground squirrel sleep for better space travel

Understanding ground squirrel sleep for better space travel

Gophers are relatives of squirrels that live on the ground in burrows, not in trees. Related to groundhawks and prairie dogs, but small, ground squirrels are used in animal physiology to study the mechanisms of sleep.

A striped ground squirrel in a Texas meadow.

A striped ground squirrel in a Texas meadow.

Photo: iStock

These rodents, like bears, stop eating in the winter and survive until the spring, thanks to the fat reserves they store during the summer months.

This type of prolonged fasting and inactivity may significantly reduce muscle mass and function in these dormant animals, but they do not experience this rule. However, how they avoid it remains a mystery.Explains the press release issued by UdeM.

This was before Matthew Reagan’s work on the striped ground squirrel (Ictidomies trichocemlinatus) It is found in the Prairie States and some US states.

His study was published in the journal ScienceDisgusting (New window)Disgusting (In English), published in the 1980s confirms the recycling theory of urea nitrogen and how it can have an impact on the lives of astronauts in space.

According to this theory, hibernators recycle the nitrogen found in urea using a metabolic technique in their gut microbiota, which is usually excreted in the urine and used to make new tissue proteins.Mentioned in the press release.


  • The word squirrel is derived from Greek words Sperm, SeedAnd philosophies, Who like
  • When they are idle, the ground squirrel’s heart rate is 200 to 5 beats per minute. They breathe only once every 5-10 minutes.

Matthew Reagan’s experiments were performed three times a year on ground squirrels with and without intestinal microbiota:

  • In summer, they are active but not dormant;
  • At the beginning of winter, a month asleep, when they were fasting;
  • At the end of the winter, they were fasting and asleep for four months.

Importantly, studies show that ground squirrels with intestinal microbiota (made up of 100 trillion bacteria) excrete nitrogen from urea during sleep.

Importantly, squirrels with intestinal microbiota did not show signs of urea nitrogen depletion. […]Ensures that this process depends entirely on the ability of intestinal bacteria to decompose urea, which cannot be done by squirrels.Says the researcher.

This work has found that the addition of urea nitrogen to squirrel tissue proteins is higher in late winter and that urea nitrogen recovery is more active as dormancy progresses.

In addition, bacteria in the gut use urea nitrogen to make new proteins, which is useful for them because they are as dormant as their hosts.

Thus, both the squirrel and its bacteria benefit from the removal of urea nitrogen, making this process a true symbiosis.The press release continues.

The fact of the matter is that squirrels are well awake in the spring and ready for the breeding season.

It is a time of intense physical activity for both men and women […]. Tissue function, especially muscle tissue function, is critical to the success of the mating season.

A quote Matthew Reagan

Space travel

Theoretically, according to Matthew Reagan, confirming the urea nitrogen recycling theory would help astronauts. To reduce the muscle loss caused by the suppression of protein synthesis induced by micro-gravity, they are currently trying to cope with intense exercise..

Quebec astronaut David Saint-Jack trained in space.

Quebec astronaut David Saint-Jack trains in space.

Photo: Radio-Canada

If a way is found to enhance the astronauts’ muscle protein synthesis processes by removing nitrogen from the urea, they will be able to maintain their muscle position during long deep space missions on spacecraft that are too small for conventional exercise equipment.That is explained in that press release.

Since we know which muscle proteins are lost during space travel, these proteins can be compared to proteins that are enhanced by the clearance of urea nitrogen during sleep.

More work

Although theoretically possible […] Changing this mechanism requires a lot of extra work […] To man, Mr. Reagan adds. Nevertheless, the researcher was inspired by the results of another study from the early 1990s, which shows that humans can recycle small amounts of urea nitrogen through the same process.

Indicates that it is in the required mechanism. You need to improve itThe biologist who continues his work concludes thanks to a grant from the Canadian Space Agency.

In addition to the impacts on space travel and the health of astronauts, the discovery could have an impact on Earth for hundreds of millions of people who suffer from wasted muscle mass due to malnutrition or the aging process.

Leave a Reply

Your email address will not be published. Required fields are marked *