Hibernating animals consume a few percent less oxygen than normal and become hypothermic, a few degrees higher than the outside air temperature, but spontaneously return to their original state without causing tissue damage.Such "controlled hypometabolism" can be expected to be clinically applied because it can avoid damage to tissues caused by trauma and diseases.However, since mice and rats normally used for experimental animals do not hibernate, the mechanism of hibernation was unknown.

　In this study, we found that excitement of nerve cells in a part of the mouse brain (hypothalamus) significantly reduced the body temperature and metabolism of mice for several days.This group of nerve cells was named Q nerve (dormant-inducing nerve), and the hypometabolism caused by stimulation of this Q nerve was named QIH.

　When the mice were in QIH, movement and feeding almost disappeared, and the body temperature set point (the temperature set by the brain for maintaining a constant body temperature) decreased.No abnormalities were observed before and after QIH in the measurement of motor ability and memory and the observation of tissues of internal organs, and the condition was very similar to hibernation.Furthermore, when the Q nerve of rat, which is a kind of non-diapausing rodent, was excited, long-term and reversible hypometabolism was confirmed as in mice.

　This time, since it was possible to induce hibernation-like states in animals that normally do not hibernate, it is possible that humans will also induce hibernation.If artificial hibernation is realized, the oxygen demand of body tissues can be greatly reduced, so it is highly applicable in the medical field such as transportation of critically ill patients and stock of regenerated organs.In the future, it will contribute to humankind's advance into space.

Paper information:[Nature] A discrete neuronal circuit induces a hibernation-like state in rodents