CANNABIS 'IS STROKE HOPE'

Extracts of the marijuana plant could one day be routinely used to prevent
brain damage after stroke, according to United States government
scientists.

A team led by the British-born biologist Aidan Hampson, at the US National
Institute for Mental Health, in Maryland, has discovered that two active
components of cannabis - compounds called THC and cannabidiol - will each
act to prevent damage to brain tissue placed in laboratory dishes.

The experiments, to be reported next week in the proceedings of the
National Academy of Sciences, reveal an unexpected potential use for a drug
known for centuries to have valuable medical properties. The discovery is
likely to increase pressure to make marijuana and its derivatives more
widely available for use on prescription.

Already, a House of Lords committee is considering the issue, the British
Medical Association has reported on the drug's virtues and the Royal
Pharmacological Society is looking into the matter.

Cannabis was widely used centuries ago. There is archaeological evidence
from the Stone Age of cannabis being used to ease birth pains. It is known
to suppress nausea for patients on cancer chemotherapy, relieve pain and
muscle spasm for multiple sclerosis sufferers, and reduce pressure in the
eye for people with glaucoma.

Dr Hampson's study has focused on cannabidiol, rather than the psychoactive
chemical THC, because this substance has no side-effects. He stumbled on
the finding while trying to find out why the human brain had so many
"receptors" for cannabis compounds and what the receptor system was
designed to do.

"There are almost as many cannabinoid receptors as there are of any major
neurotransmitter, so while no one knows what it does, it seems to be pretty
important."

Stroke victims suffer a blood clot which starves brain cells of glucose and
oxygen, and sets off a cascade of chemical reactions which destroys cells.
He found that both cannabis compounds seemed to block the destructive
process. Some drugs work well in test tubes, but ail in living creatures
because they do not reach the target. Cannabis compounds go straight to the
brain.

The results suggest that cannabidiol could also become a treatment for
other neurological disorders, such as Parkinson's and Alzheimer's diseases.
Dr Hampson said: "We have something that passes the brain barrier easily,
has low toxicity, and appears to be working in the animal trials. So I
think we have a good chance."

Checked-by: (Joel W. Johnson)