X-Message-Number: 5604
From: 
Date: Tue, 16 Jan 1996 14:33:57 -0500
Subject: SCI. CRYONICS evidence

Ralph Dratman (Cryonet #5599) asks a couple of questions that he (and
probably other new readers) would like answered, concerning the state of the
art in cryonics and the opinions and evidence offered by cryobiologists. Here
is a very brief and partial summary from my perspective: 

1. Why can human embryos be revived after freezing but not adult mammals? 

Generally, small or dispersed specimens are easier to freeze and revive than
large and "solid" ones. This is partly owing to the fact that it is easier to
do uniform and controlled cooling and warming in these cases, as well as
uniform and controlled perfusion. Further, there are usually fewer types of
tissue involved, so less need to compromise among different optimum
procedures for different types of tissue. Also, young specimens have more
capacity for self repair, hence can tolerate more damage.
Also, water that may be withdrawn from the specimen during freezing forms
crystals only in the environment, not in adjacent tissues. Nevertheless, a
few non-microscopic "solid" adult mammalian organs have been revived from
liquid nitrogen temperature, including the 
rat ovary and rat parathyroid. 

2. Revival of neural tissue after deep freeze?

Hamsters have been revived after about half the water in the brains had
changed to ice; apparently there was persistence of memory and personality,
although the evidence for this is not clear-cut. Many types of mammalian
brain tissue have been revived or partly revived after complete freezing and
cooling down to dry ice or liquid nitrogen temperature. (And many  types have
shown persistence of some indicia of life even after many hours of death and
warm ischemia.) In particular, synaptosomes have been shown to be relatively
freeze-hardy.

Suda, Kito and Adachi in the Sixties froze cat brains, after perfusing with a
glycerol based solution, stored them at relatively high sub-zero temperature,
and got pretty good corticograms (encephalograms) after thawing; later they
got less impressive results after storing for longer periods at lower
temperatures. Last year Dr. Yuri Pichugin and associates in the Ukraine
(funded by the Immortalist Society and the Cryonics Institute) got both
spontaneous and induced bioelectric activity (BEA) in rabbit brain pieces
rewarmed from liquid nitrogen temperature, if they had been perfused with a
glycerol based solution; there was no BEA in the unperfused controls. Follow
up-work continues.
(Dr. Pichugin et al also confirmed absence of cracking in sheep heads
perfused and frozen by a procedure tried at Cryonics Institute.)

>From a broad, theoretical perspective, in the absence of full success in the
laboratory, the main question is whether sufficient STRUCTURE remains in a
frozen brain to allow future repair by advanced technology--i.e., to allow
inference of all essential details of the intact brain. Several technical
discussions along this line include one by Dr. Ralph Merkle, available from
Alcor. <>

3. On what do I base my statement that most cryobiologists dismiss the
probability of revival of current cryostasis patients as "negligible" but
never offer a calculation of probability (or indeed any relevant evidence of
any kind)?

These opinions of most cryobiologists have come to me sometimes in private
communications, more often through the media. The detractors will never hold
still for a serious discussion or a rebuttal; they want only sound bites for
public dissemination, not actual presentation and evaluation of evidence. If
any highly credentialed cryobiologist will come to Arizona (where my wife and
I now live--even though I am still president of the Cryonics Institute in
Michigan--and where Alcor is located), and will enter into a public debate
for one full day, the Cryonics Institute will pay first class travel and
hotel expenses plus $1,000 honorarium. And we will consider extending this
offer to two or three such cryobiologists, so they won't feel outnumbered.

The only published statement on cryonics in a technical book or journal by a
prominent cryobiologist who was not in cryonics, as far as I know, was that
by the grand old lady of British cryobiology, the late Audrey Smith. In the
1970 book she edited and partly wrote, CURRENT TRENDS IN CRYOBIOLOGY, she
wrote a negative opinion, including the following quotation--but if the
reader will note how carefully hedged it is, its force dissipates. She said
(emphasis added):

"There is, therefore, LITTLE chance that a WHOLE BODY frozen SEVERAL HOURS OR
DAYS after death of the animal could be revived either at the PRESENT TIME or
at any FORESEEABLE time in the NEAR FUTURE..."  

As far as I know, the only long exposition publicly made by a prominent
cryobiologist not opposed to cryonics is in a Declaration filed with the
Superior Court of California (Riverside) in connection with the Dora Kent
case in 1988, Case No. 191277. This is required reading for anyone who is
serious about the topic. The Immortalist Society has copies of this (and
including other favorable declarations by scientists in related fields). It
also includes a long list of literature references, which I omit here.

Other recent improvements in procedures have been reported by BioPreservation
and  by BioTime corporations. We are also awaiting the expected publication
in CRYOBIOLOGY of the reported complete success by a Dr. Visser in South
Africa in reviving rat hearts after rewarming from liquid nitrogen
temperature.

Robert Ettinger
Cryonics Institute
Immortalist Society


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