人工冬眠、実現できるかも　マウス実験で実証―筑波大など

　脳の特定の神経回路を刺激することで、本来は冬眠しないマウスを冬眠状態にすることに筑波大や理化学研究所の研究チームが成功した。代謝が極端に低下する冬眠状態を人工的に起こすことができれば、脳疾患や肺炎などの治療への応用が期待できるという。論文は１１日、英科学誌ネイチャーに掲載された。
　冬眠中の動物は酸素消費量が正常時の数パーセントまで低下。体温も外気温程度まで下がり代謝が大幅に低下するが、春になるとなんの後遺症もなく元に戻る。
　冬眠しないヒトやマウスでも、脳梗塞や心臓疾患、肺炎などで酸素供給能力が落ちた際、人工的に冬眠させて全身の酸素消費量を減らせれば、組織の障害を防げると期待されている。
　筑波大の櫻井武教授らは、マウスの脳の視床下部にある特定の神経細胞群が、ＣＮＯという物質と反応するよう遺伝子を操作。このマウスにＣＮＯを投与すると、体温や酸素消費量が急激に低下し冬眠のような状態になった。（2020/06/11-18:14）

A team of Japanese researchers has succeeded in inducing a hibernation-like state in mice by stimulating a certain neural circuit in their brain, suggesting that animals could be put into such a state artificially.
   Artificial hibernation, if realized, could be applied to the treatment of illnesses such as brain disease and pneumonia.
   Animals in hibernation need only a fraction of the oxygen they normally consume. Their body temperature also falls to levels around the external temperature, with a substantial decrease in their metabolism. When spring comes, however, they wake up with no aftereffect.
   If mice and humans, which both do not hibernate, are artificially put into a hibernation-like state when their ability to supply oxygen to the body decreases because of diseases such as cerebral infarction, heart disease and pneumonia, their oxygen consumption could be reduced and tissue damage could be avoided.
   According to an article on its study, published in British science journal Nature on Thursday, the team of the University of Tsukuba and government-affiliated research institute Riken altered a gene in mice so that a certain group of neurons in the hypothalamus in their brain would react to a substance called CNO.