X-Message-Number: 326 From att!garnet.berkeley.edu!quaife Sat May 11 07:27:03 PDT 1991 Date: Sat, 11 May 91 07:27:03 PDT From: Message-Id: <> To: Subject: Freezing brains Breakthrough in Cryopreservation of Mammalian Brains Art Quaife, Ph.D. President, Trans Time Inc. Our biologists, particularly Drs. Hal Sternberg and Paul Segall, (who are also principals in the newly-formed BioTime) currently perform about 25 freezing experiments on hamsters per month -- nearly one per day. Recently we have made an important discovery that may significantly improve cryonic suspension procedures. We have developed new cryoprotective solutions and a protocol that have resulted in what appears, under a dissecting microscope and using the naked eye, to be EXCELLENT anatomical preservation of the hamster brain. We perfused hamsters with the newly developed cryoprotective solutions and froze them down to -80 degrees C for one to three days. The hamsters were then thawed using intermittent microwave pulsing. We replaced the cryoprotective solution with a more physiologic solution, and reperfused blood. Upon autopsy of the brain and gross inspection, the circulatory system of these hamsters appears intact. The brain is dehydrated, not edematous. Previous attempts had resulted in a lack of blood perfusion to certain brain regions, while areas that received blood had become very ruddy (strong generalized reddish tinge) and/or pox-like (distinct red spots) in appearance. This was probably due to broken blood vessels caused by freezing using inappropriate protocols and cryoprotective solutions. At the appropriate time we may have these post-frozen brains stained and examined by a professional histologist to determine to what degree their histology is normal. I have color photographs of a brain frozen using our new procedure, compared to a brain frozen using a 3 molar glycerol solution. The difference is VERY dramatic. I will be happy to send you a color photocopy of these prints, if you send me your postal mail address. Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=326