gautam at mcbl.iisc.ernet.in
Sat Nov 20 23:10:15 EST 1999
I think "necrosis' has generate quite a few mails.
I am not an expert, but having worked in the area of apoptosis for the
last 8 years please allow me put in my views on necrosis.
Whether it is in tissue (in vivo) or outside (in vitro) in a tissue
culture system, I strongly feel that one should look strictly only at some
distinct "biochemical marker" rather than going and searching at molecular
level. I have realised that everyone now-a-days think of only using the
RNA or DNA system to address/answer a question. Why not look at the
biochemical events?!?! Because if one stops for a while and thinks a bit,
they will realise that it is the biochemical events that govern both these
pehnomena (if you wish to name them) of necrosis and apoptosis.
And please do not forget the last stage of apoptosis is termed as
So I find that someone here said, how does one define/seperate necrosis
from apoptosis ??
Well, let me give a few examples - release of acidic enzymes, lysosomal
enzymes, RANases are some of the markers that you will find are found only
in an event of necrosis and not in apoptosis. Also one shall "not" find
nuclear enzymes or "nuclear releases" in an event of necrosis. Ofcourse
these latter(nuclear stuff) you will be able to observe only in a tissue
culture system where "slow" necrosis is taking place.
And as a last point - if you can observe "necrosis" in a SINGLE cell in
tissue culture - well you will get a Nature/Science/Cell paper. Because it
has never been reported till date, as far as I am aware of. Because ask a
question, people who observe apoptosis in a single cell in an invitro
system (tissue culture) does such an event actually ever happen in
best of luck with your search with "necrosis"...........
On 20 Nov 1999, Ian A. York wrote:
> In article <383780C0.C63DD8 at home.com>, Menoret <menoret at home.com> wrote:
> >Well, I think you are probably right. For me necrosis without any trace
> >of apoptosis has to be a violent phenomenon, like immediate tissue
> >destruction. Most of the so-called necrosis observed in vivo looks like
> >different kind of post apoptotic cell death. What is your definition of
> >necrosis ? Are you talking of a cell or of a tissue ?
> We're definitely talking about cells, as in cultured cells. The
> definition of necrosis (if there is one) seems to be a negative one--cell
> death that isn't apoptosis. Of course, apoptosis used to be defined as
> cell death that isn't necrosis, but I think the concept of apoptosis is
> more based on molecular events now.
> I don't really know what necrosis is at the single-cell level. I think
> of things like reactive oxygen species or anoxia, for most cells, leading
> to a violent cell death, but one that takes several hours to occur--not as
> simple as being torn from limb to limb. The lack of a good definition is
> probably one of the problems we're facing in this question.
> Ian York (iayork at panix.com) <http://www.panix.com/~iayork/>
> "-but as he was a York, I am rather inclined to suppose him a
> very respectable Man." -Jane Austen, The History of England
More information about the Methods