(Caracas, April 17. News24). – A group of researchers has managed to restore certain neuronal functions in the brains of dead pigs for several hours, a milestone worthy of science fiction, which in no way proves that the resurrection is possible.
A study published on Wednesday in the journal Nature shows that the brains studied did not detect "no electrical activity that would be associated with the phenomenon of consciousness or perception".
"They are not brains but brains whose cells are active", Says one of the study's authors, Nenad Sestan.
According to this researcher at Yale University, these studies show that "we underestimated the ability of cellular brain reconstruction".
In addition, they suggest that the deterioration of neurons as a consequencecessation of blood flow can be a long-term process", According to the Nature statement.
Mammalian brains are very sensitive to the drop in oxygen delivered by the blood. Therefore, when the flow is interrupted, the brain stops to oxygenate and the damage is irreversible.
Researchers used 32 brains of dead pigs for 4 hours. Thanks to the pump system called BrainEx, They were irrigated for six hours with a solution at a temperature equivalent to that of body temperature (37 degrees).
This blood replacement solution was designed to oxygenate tissues and protect them from degradation resulting from the cessation of blood flow.
The results were overwhelming: decreased destruction of brain cells, preservation of circulatory function and even restoration of synaptic activity (electrical or chemical signals in the area of contact between neurons).
According to the researchers, the study may allow a better understanding of the brain by investigating how it degrades post-mortem. This would also open the way to future techniques of brain preservation after a heart attacke.g.
Theoretically, in the long run, it can be used to resuscitate a dead brain, something impossible at the moment.
– Live or not? –
"The direct challenges resulting from these results are above all ethical", Says Professor David Menon of the University of Cambrigde, who did not participate in the study.
Re-open the question "what makes an animal or a man alive", say other scientists in a commentary published in parallel in Nature.
"In this study, pig brains that did not receive oxygen, glucose or other nutrients for 4 hours were used. Because it opens up possibilities that were previously unimaginable, "according to Riva Farahana, Henry Greely and Charles Giattino, respectively professor of philosophy and neurobiologists.
According to these experts, the study may highlight two scientific principles.
"First of all, the fact that neural activity and consciousness stop definitively after a few seconds or minutes of interruption of blood flow in the mammalian brain. "
"Secondly, the fact that if the blood circulation is not quickly restored, an irreversible process is activated, which leads to cell death and then to the organ," they say.
These three experts are calling for the establishment "Directives on scientific and ethical issues raised in this study".
In another commentary published by Nature, experts in the field of bioethics underline that the development of the BrainEx technique may harm organ donation in the long term.
For the transplant, most organs they are obtained from donors in the state of brain death. If you think that this state is reversibleWhat will happen with the donation?
Trio Farahana, Greely and Giattino quote the phrase from The American Promised Princess from 1987: "There is a slight difference between being almost dead and completely dead (…) Almost dead, he is still alive," says the healer in the film.
With information from AFP