Using fish proteins made in a lab, scientists have managed to preserve a pig's heart at subfreezing temperatures for 24 hours, then transplant it into another pig.
Scientists say they don't see any immediate potential for putting an entire human body in a science fiction-style deep freeze; the frogs, after all, don't stay frozen forever.
But just freezing and thawing one human organ would be a major breakthrough.
"If we can translate that into a human heart, then we'll do very well," Rubinsky said.
Now, even as researchers try to copy the frog's techniques, the freezing amphibians still haven't given up all their secrets.
Their ability to thaw puzzles scientists, who are trying to crack the process and pinpoint the trigger that restarts the frog's heart.
Whatever it is, Storey said, "it's not magic. It's physical chemistry."
Video of a wood frog thawing out from a frozen state is available on The Washington Post Web site at www.washingtonpost.com/wp-srv/mmedia/nation/120904-12v.htm.
