Rats induced into hibernation-like state | Life | Science News: But Tupone and colleagues bypassed the rats’ defenses against the cold with a compound that’s similar to adenosine, a molecule in the body that signals sleepiness. After about an hour in a room chilled to 15 Celsius, the rats grew lethargic. Their brain waves slowed, their heart rates dropped and their heart occasionally skipped beats.
The rats’ core temperature dropped from about 38� �to about 28� C, or 82� Fahrenheit, the authors report �in the Sept. 4 Journal of Neuroscience. Tupone and his colleagues measured even lower temperatures in further experiments — rats’ core body temperature reached 15� C or about 59� F. “That is a pretty amazing temperature. No one has done this before,” he says.
The rats weren’t in a coma, nor were they asleep or truly hibernating. Hibernating animals’ metabolisms plummet and their temperatures sink much lower; an Arctic ground squirrel, for instance, cools to about —3� C when it hibernates.
“It’s a new state,” Tupone says. “We don’t really know what it is.”