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stroke, that usually occurs following a rupture of a blood vessel; for
example, an aneurysm, or high blood pressure in a individual.
The second type is the one that we have worked on, which is the
infarction type. In this model, we simulate a cerebral stroke by
occluding one of the major vessels to the brain, and although there
may be some spillage of blood, it is not massive in that sense.
So, the experiences that we have are merely with the accumula-
tion of water in the tissue in the brain, which is very similar to
blood because it still takes space and you still have to get rid of it
if you want the subject to survive.
However, some experiments have been done in humans at the
University of Chicago and they show that even the spilling of the
blood into the brain can be reduced by DMSO. How it does this, no
one really knows for sure.
We noticed in our stroke model that all our animals following
occlusion of this major blood vessel had a narrowing of the blood
vessel after 17 hours. When we took the clip off this blood vessel to
allow the flow to return, this narrowing was still present, except in
the DMSO-treated animals the narrowing was not present in this
major vessel.
Because of this, we theorized that the perfusion of the blood
vessels in the posterior area of the brain which is not supplied by
this particular blood vessel was better, simply because DMSO kept
this blood vessel from narrowing down too much.
How it does this again is speculation.
So these findings, then showed that DMSO was highly more
effective than other treatments that are presently used for stroke,
for spinal cord injury, and for head injury.
In addition to this, DMSO appeared to protect nerve cells from
the actual physical disruption that occurs following injury. It did
this better than the other treatments used. This was verified by a
number of tools, including observation through the electron micro-
scope and observation through the light microscope.
The picture of how DMSO works in these systems is still highly
theoretical. Chemically, we still don't know what is happening. In
the short time that I have to summarize all this data, I don't think
I could give you an intelligent overall view, so you could under-
stand biochemically how DMSO is acting.
However, several facts do stand out, first that DMSO is extreme-
ly effective in preventing the paralysis that may ensue in these
animals following trauma to their cord; second, that DMSO can
prevent or reverse many of the pathologic signs that are seen after
brain trauma.
Third, and not least important, is that DMSO can prevent the
severe effects seen after an embolic brain stroke. This is an area
that may affect half a million people in the United States alone.
Now, we were curious to find out if there was some toxicology to
this drug. Although some toxicity studies have been done before on
various animal species, no toxicity studies had been done on the
drug after intravenous use for an acute period of time.
So, we took a series of rhesus monkeys that are phylogenetically
very close to man, and injected high doses of DMSO intravenously
for 9 days. Before and after we tested these monkeys for their
