Argon - anaesthetic mystery solved

[Przemko]

In article <2gteviINNqtp at newsman.csu.murdoch.edu.au> cummins at possum.murdoch.edu.au (Jim Cummins) writes:
>Some weeks ago I posted a query on Agon.  Our mice were falling asleep
>in 5% Argon in normal pressure air.   Turns out that all the Noble
>gases (except Helium) are anaesthetic at high pressure, in fact but for
>its cost Xenon might be the ideal anesthetic!  The puzzle was that we
>were getting effects at such low partial pressure.  
>
>It turns out that the flow rates we were using were insufficient to
>prevent back-flow from the hospital's gas disposal system, and we
>didn't have a valve in the outflow  line.  Consequently the anaesthetic
>effect  was from  a gas cocktail emanating from the operating theatres!
>
> Thanks to all who replied and helped.
>
>Jim Cummins                   
>School of Veterinary Studies
>Murdoch University
>Western Australia 6150  Tel +61-9-360 2668 Fax +61-9-310 4144
>For every complex problem there's a simple solution.  And it's wrong!

How does it work? I mean, one would think that a noble gas wouldn't
do much...

Przemko