Suspended Animation In Mice Without Freezing

Predictions Market writes "Low doses of hydrogen sulfide, the toxic gas responsible for the unpleasant odor of rotten eggs, can safely and reversibly depress both metabolism and aspects of cardiovascular function in mice, producing a suspended-animation-like state that does not depend on a reduction in body temperature and include a substantial decrease in heart rate without a drop in blood pressure. The researchers measured factors such as heart rate, blood pressure, body temperature, respiration, and physical activity in normal mice exposed to low-dose (80 ppm) hydrogen sulfide for several hours. In all the mice, metabolic measurements such as consumption of oxygen and production of carbon dioxide dropped in as little as 10 minutes after they began inhaling hydrogen sulfide, remained low as long as the gas was administered, and returned to normal within 30 minutes of the resumption of a normal air supply. 'Producing a reversible hypometabolic state could allow organ function to be preserved when oxygen supply is limited, such as after a traumatic injury,' says the lead author of the study. 'We don't know yet if these results will be transferable to humans, so our next step will be to study the use of hydrogen sulfide in larger mammals.' The full report is available online."

No, that isn't the next step

[QuantumG]

'We don't know yet if these results will be transferable to humans, so our next step will be to study the use of hydrogen sulfide in larger mammals.'

Uhh, no. The next step is to determine if this is the kind of suspended animation that is good for anything. If the mice enter a reduced metabolic state and then, after 3 days, die, well that's not terribly useful for anything. If, however, the mice managed to live 10 times the usual rodent lifetime then that's something... not terribly great.. but something. Try to make it so the mice are recoverable after 1000x the usual lifespan and you might have something useful.

True but...

[Sterrance]

many things that can save our lives (major surgery, chemotherapy) also leaves us wanting to die. Just because something is horribly painful doesn't mean we should avoid it.

I think that's not what they had in mind

[Moraelin]

While that's insightful in its own right, from reading the summary, I get the impression that they're not aiming for the kind of suspended animation where you freeze someone for 1000 years and wake them up later. Doing that at room temperature would be kinda dangerous anyway, since if you slowed their immune system 10 times they'll rot alive sooner or later anyway.

I'm getting the impression that this is more for rushing you to a hospital when they picked you up half-dead and bled half-dry off the side of the road.

If you're in serious shock for example, if the other mechanisms still work, the body will try to keep the brain alive, even at the cost of cutting off oxygen supply to the other internal organs. Which decay very fast. (Muscles have their own oxygen reserves, so they tend to survive, your liver doesn't.) Cells run out of oxygen and essentially commit suicide in an orderly fashion, i.e., apoptosis [wikipedia.org].

If it doesn't have enough even for the brain, which is often the case, the damage is irreversible and often fatal. Very fast.

So if they can slow your metabolism a lot, that might just give them extra time to haul you into ER. It might just turn that 5 minute rush before your brain starts getting massive damage, into, say, 50 minutes. Which might just do the trick.

I.e., briefly: it's not for colonizing Alpha Centauri, mate, it's just while they haul you to ER.

Send people to Mars or Alpha Centauri

[VincenzoRomano]

You can also enable long term space travels with such a finding!

Re:So does this mean...

[rubycodez]

only if there is high sulfide content.

mere loud and long exhibitionist expulsions won't cut it, they need to *stink*. silent but deadly wins over foghorn-like showboating.

Just wondering...

[o'reor]

... some towns around the planet have quite a reputation for having a high sulphur rate in their atmosphere (Rotorua [wikipedia.org] in NZ is nicknamed "Sulphur City" because of that -- you can actually smell it when you're getting close to the town, and it takes a little while to get used to breathing that air !). Why don't they conduct a survey on the metabolism of the people naturally exposed to those gases ?

Re:I declare this year of the mouse!

[philspear]

Looks like we can do more for mice, than for humans

You could do more for humans if there weren't all these "ethical objections" to research which would probably kill people, or to making transgenic humans. Fortunately, only humans object to human research, (just as only mice and hippies object to mouse research) and so our human probing experiments are proceeding as planned.