By tracing radioactive pollution created by the nuclear tests of the 1950s, researchers have settled the question of whether the human heart creates new cells during a person's lifespan.
“The dogma has always been that cell division in the heart pretty much stops after birth.... In medical school, we teach that you’ll die with the heart cells you’re born with” [Science News]
, comments cardiovascular expert Charles Murry. However, a new study has overturned this dogma, and found that the heart does regenerate, albeit slowly.
Cell turnover rates can easily be measured in animals by making their cells radioactive and seeing how fast they are replaced. Such an experiment, called pulse-labeling, could not ethically be done in people. But Dr. Frisen realized several years ago that nuclear weapons tested in the atmosphere until 1963 had in fact labeled the cells of the entire world’s population [The New York Times].
The ...
