> astounded to hear Lovelock's claim that after his
> unpatented invention (in the '50s? ' 40s?) of the microwave oven - or at
> least of using microwaves to thaw frozen stuff - certain researchers in the
> '50s successfully revived small frozen mammals by that method.
> How pristine the animals' neurology was and how long they lasted after
> revival wasn't made clear, but Lovelock was explicit about their chilly
> temporary state - frozen hamsters, he said, were quite solid; you could
> knock them against the lab bench. After thawing, they'd run around.
Paul Wakfer responded, and allowed me to cc to these lists:
========================
The people at Biotime do this regularly. Don't forget the hamsters are
"designed" to hibernate and go to very low temperatures in the winter.
Yes, they can actually withstand a percentage of their brain water
turned to ice (I forget how much). In addition, any mammal when cooled
to near the ice point becomes stiff as a board and might appear to be
quite solid. This is because the body's structural elements are mostly
lipid and get very vicous/solid at that temperature. The dogs that 21CM
does deep hypothermia experiments on (5+ hours at 2-3'C) feel like that.
And yes you could probably knock them against a lab bench without much
damage to them (merely a small surface bruise when they were rewarmed)
because the flesh is neither brittle nor very crushable.
However, unfortunately, this and frozen frogs, fish, etc. are very
little help to our needs in cryonics. The main reason for this is that
chemistry, metabolism and biology are still proceeding and degradation
is still taking place. For example, if you took any of the species which
freeze and kept it in that state for even twice as long as the longest
that it normally is in that state, the vast majority would not survive.
Certainly, if you went out to 10 times, *none* would survive. In fact,
the only animals which can stand very long periods of "suspended
animation" are very small species which can completely desiccate (brine
shrimp, tardigrades, etc).
> I have a lot of respect for Lovelock's integrity and ingenuity. Yet this
> claim appears to surpass anything that current cryonics specialists seem
> able to replicate.
That's only because we believe that this approach is a waste of our
scarce resources. If we had enough money for suspended animation
research, we would certainly be looking into the possibility of using or
modifying animal anti-ice compounds.
===================
Charles Platt told me (and I quote without explicit permission):
===================
Undoubtedly the experiments he is referring to were Audrey Smith's, with
hamsters. Extremities of the hamsters were indeed frozen solid, but
internally the hamsters had to contain less than, I think, 60 percent
ice, otherwise they didn't revive. Even the hamsters that were revived
tended not to live very long, as a result of many ruptured blood vessels
and gastrointestinal bleeding.
A "diathermy" unit was used to thaw the hamsters. As I recall, this was
an early device using radio-frequency (RF) radiation. I think it's
actually a little lower in the spectrum than microwaves, but is virtually
the same thing. Originally it was used to apply heat to injured joints
and muscles (I think).
===================
I replied:
According to Lovelock, they started out by applying a red-hot spoon to the
chest of the chilled animal to kickstart its heart. Left nasty burns
(d'oh), so he came up with his kinder, gentler gadget.
Thanks to both gentlemen for their information.
Damien Broderick