More Co2 = less brains?

Nate dnawten at ix.netcom.com
Mon Feb 10 22:40:32 EST 1997



Jay Hanson <j at qmail.com> wrote in article <32FFA793.A6F at qmail.com>...
> Patrick Juola wrote:
> 
> > >Are you saying that the a higher CO2 level in a crowded room
> > >does NOT cause drowsiness?
> > 
> > I'm saying that it does not do so by binding more tightly to the blood
> > hemoglobin than oxygen does.
> 
> Hi Again Patrick,
> 
> I don't know anything about this stuff.
> 
> Do you agree with Ralph that increased CO2 -- one way or
> another -- causes the drowsiness that overcomes people in
> overcrowded lecture-halls?
> 
> Or do you have no opinion on this aspect of the question?
> 
> Jay
> 

Hope I'm not unwelcome in chiming in on this but regarding the displacement
of O2 by CO2 on hemoglobin, this is physically impossible.  CO2 binds to
the "globin" part of Hb (23% of all CO2 is carried this way, about 70% is
carried in the plasma) while O2 is carried by the "heme" portion (98% of
all O2 binds to Fe++ ions).  So theoretically both CO2 and O2 can can be
carried on the same Hb meaning that an increase of CO2 by itself probably
will not cause drowziness.  It probably has to do moreso with an inadequate
supply of O2 than anything else.  

A good example of this would be if someone suffocated in a plastic bag. 
Drowziness, unconsciousness and eventual death wouldn't be a result of the
increased CO2 per se, but due to the lack of oxygen.

Hope this answers your question.

Nate



More information about the Neur-sci mailing list