X-Message-Number: 26370 Date: Wed, 22 Jun 2005 08:57:32 -0400 From: Thomas Donaldson <> Subject: comments for Doug and Basie A few comments for Doug and Basie: For Doug Skrecky: Whether or not your experiment shows the falsity of the free radical theory of aging depends a lot on what you mean by "the free radical theory of aging". If you mean that any free radical inhibitor will lengthen lifespan, then your work with cerium oxide, plus other work with various other antioxidants extending back at least to experiments using Vitamin C with guinea pigs, definitely shows that not every free radical inhibitor will work against aging. If you claim that NO free radical inhibitor works against aging, you have a problem: even Vitamin E shows a small but verifiable effect, and others such as BHT do so too. Some claim that these antioxidants don't work against aging because they didn't increase maximum lifespan. If an experiment is done with a small number of animals, you may get an increase in average lifespan but (because you just don't have enough animals to show it) no increase in maximum lifespan. It's interesting here that Anna Aslan got an increase in maximum lifespan when she tested her procaine mixture --- on 900 test animals and 900 controls. I doubt she would have gotten such an increase if she'd used only 50 test and 50 controls. The effect of SOME antioxidants needs more study. And anyone (of which there are unfortunately too many) who sells various antioxidants on the ground that they will increase lifespans should make sure they've been tested and shown to do that. For Basie: I don't really know what you're getting at here. Even though glutamate is usually excitatory, in proper circumstances it can be inhibitory; and the same may be said of different types of GABA (gamma-aminobutyric acid) in reverse: usually inhibitory but can be excitatory. Both transmitters cause a relatively short and primitive kind of memory, which basically persists until the metabolism of the neurons involved produces new chemical which act to keep that memory active for longer. (If you like jargon, the kinds of short term memory are called LTP --- long term potentiation, and LTD -- long term depression). That in some brain areas, including the hippocampus, glutamate can become inhibitory and GABA can become excitatory has been known for several years now. Anyone who reads PERIASTRON will remember this fact. Best wishes and long long life for all, Thomas Donaldson Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=26370