I would doubt brain damagae occurs in this situation. Your reserves of O2 in
your blood would last for 1 or 2 minutes. I think that you would become
unconscious beforre any brain damage occurs, and begin breathing while you
are unconscious. It is not unusual for little kids to have breath holding
spells lasting a minute or two and turning blue (Kids and adults, do not try
this at home.) For the same reason, I doubt that inhaling nitrous oxide
would cause damage through hypoxia.
However, there are other ways nitrous oxide could damage brain cells.
Nitrous oxide is involved in brain function, and I have little doubt too
much can cause damage. i do recommend that you do not use this
recreationally. And if you become somewhat disoriented, there is no
guarentee that you respiratory centers will kick back in and you will
continue to breath.
The brain is damaged by lack of oxygen (called hypoxia), through several
mechanisms. Many of these involve too much calcium, which leaks into the
cell. Because there is no oxygen, the brain cells cannot make energy (ATP).
Then the calium that normally comes into the cells cannot be pumped out.
This is real bad.
Too much calcium kills mitocondria, called the powerhouses of the cells. No
energy, no life. Another way calcium is able to kill cells is it triggers
something called programmed cell death (also called apotosis). This causes
otherwise healthy cells to give up and go quietly.
Together, basically, hypoxia causes brain cells to die. Because of the high
needs of the brain for oxygen and energy, the brain cells are really
sensitive to a lack of oxygen, and give up quickly, compared to say,
intestinal cells or muscle cells.
Neogen wrote in message <36fd1aee.4153210 at nntpserver.swip.net>...
>I'm wondering about for how long the brain can go w/o oxygen, before
>braindamage occurs? (And also, how the damage occurs..)
>>For example, if I breathe out as much air as possible, in less than 10
>seconds I will feel the need to inhale. Does this mean that if I could go
>longer w/o inhaling, something ..bad would happend?
>>I've read reports of people inhaling pure N2O (as opposed to the dental
>70% mix, or whatever amount it is :) and holding it in for minutes, would
>this mean that some sort of damage occurs?