Rabbit brain structure preserved after cryopreservation

[AstroMech]

I’m not sure if people have seen this but 21st Century Medicine recently won a prize for recovering a rabbit brain after cryopreservation:

http://www.newsweek.com/rabbit-brain-fi ... ion-424913

It wasn't viable because of toxicity of the cryoprotectants but the brain structure was preserved. They were also able to prevent brain shrinkage which I don't think was done before.

More details including links to some of the procedures they used:

http://www.brainpreservation.org/small- ... ouncement/

[RibJig]

Thanks for link!
Article doesn't specify if rabbit naturally died,
or was healthy & sacrificed.
Also see correction at end about preserved vs. recovered.

"The current process used to cryogenically preserve human brains has been criticized for causing massive dehydration to the brain and crushing neural connections. It is believed that this process is too damaging to allow for successful future revival."

So will Alcor immediately switch to aldehyde method !!

[AstroMech]

That's a good question - I don't know how the rabbit died either. I can imagine that a rabbit killed specifically for an experiment may be easier to preserve than one that was sick and had tumors, circulation problems etc.

The results are in a scientific journal so Alcor should be able to see them, and I'm sure those people talk to one another (I hope?). I wonder if there are specific challenges in using the aldehyde method on a larger organism? It sounds like it's a big improvement on the current method though!

[AstroMech]

Oh - I just noticed that the most recent edition of Cryonics magazine has an article by Ralph Merkle in which he points out that Alcor hasn't adopted the new method (with gluteraldehyde) yet because it reduces viability because of increased toxicity (the second half of the article, on page 6). It says that they have favored increasing viability over reducing dehydration.

[johnkclark]

Hi ​ AstroMech

"​the most recent edition of Cryonics magazine has an article by Ralph Merkle in which he points out that Alcor hasn't adopted the new method (with gluteraldehyde) yet because it reduces viability​"​

​Since no mammal using either method has been brought back to life from liquid nitrogen temperatures that does not seem like a valid point to me.​

​"​because of increased toxicity (the second half of the article, on page 6). It says that they have favored increasing viability over reducing dehydration.​"​

Gluteraldehyde is just wart removing lotion, you can get it at the drugstore over the counter without a prescription. They did use Osmium tetroxide​ and that is pretty toxic but it is not part of the preservation process itself, ​it was used to stain brain slices so they could take pictures with an electron microscope, it is used in research but you wouldn't use it if you were actually freezing a person, there would be no need. And by the way, those electron microscope pictures were far far sharper and more detailed than anything Alcor's current method of preservation can achieve. Why Alcor doesn't switch over to the better way is a mystery to me.

John K Clark