X-Message-Number: 7501 Date: Tue, 14 Jan 1997 09:55:49 -0800 (PST) From: Doug Skrecky <> Subject: the merit of glucose In Message #7456 "Henry R. Hirsch" <> wrote: > 1. Has glucose been studied as a cryoprotectant in humans or > other mammals? > Background: Glucose serves as the major cryoprotectant in the > freeze-tolerant frog R. Sylvatica (1). Although glucose is part of R. Sylvatica's adaptions to freezing, strangely enough glucose itself is not a cryoprotectant. For example glucose given to the non-freeze tolerant leopard frog does not increase its freeze viability. (Am. J. Physiol 265: R721-R725 1993 > 2. Has glucose been studied as a "dryoprotectant", i. e. a > substance which stabilizes cell membranes against dehydration? Although glucose is not a cryoprotectant, it is an "dryoprotectant" or anhydroprotectant. For example by including polyethylene glycol to protect against freezing injury, very small amounts of glucose fully protect labile proteins during freeze-drying. (Archives of Biochemistry and Biophysics 303(2) 456-473 June 1993) Although most anhydroprotectants are also very effective cryoprotectants, they are also incapable of readily penetrating tissue. No matter how beneficial anhydroprotectant/cryoprotectants such as sucrose or trehalose are, if they can not penetrate tissue, they will not be able to protect against anything. Thus glucose stands in a very interesting position, which when combined with a permeable cryoprotectant, can offer a measure of both freezing and freeze-drying protection. > Background: According to Hochachka and Guppy (2), well-known > cryoprotectants provide such stability and are essential to the > survival of anhydrobiotes. If glucose or another suitable agent > were to function similarly in humans, freeze-drying would provide > a desirable alternative to low-temperature suspension. Maintenance > of the patient would be much simpler. "Passive encapsulation in a > sealed container would replace "active" liquid nitrogen storage. I view cryonics as a leaky rowboat. It is familiar technology and as such is widely accepted as the only means for the dead to cross an ocean of time till reanimination technology becomes available. Most choose to believe that the time elapsed will be relatively short (50-200 years) since if it is not the the rowboat will have no chance to reach the opposite coast before sinking. By comparison I view freeze-drying as a battleship. Rather unfamiliar and unconventional, but fully able to combat vast stretches of time till the distant future is reached on the other side of that ocean of time. Properly implimented freeze-drying could act as a time machine to help the deceased travel millenia farther into the future than cryonics can, there to await judgement. We have the technology. We have the knowledge to create the world's first freeze-dried corpse, one where resurrection in the far future is at least a possibility. Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=7501