THE cannabis debate was thrown wide open today after new research claimed the main active ingredient in the drug can protect arteries against the risk of strokes and heart attacks.
But scientists warn that simply smoking cannabis does not offer the same benefit and may actually damage the heart.
THC, or delta-9-tetrahydrocannabinol, is known to affect the brain and make cannabis-users "high". The new research shows that it also has an influence on blood vessels.
A study of mice revealed that the compound blocks the process of inflammation which is largely responsible for the narrowing of arteries.
Inflammation combines with fatty deposits to produce obstructive "plaques", a condition known as atherosclerosis. These can block arteries to the heart, causing angina and heart attacks, or to the brain, leading to strokes.
The scientists, led by Dr Francois Mach from Geneva University Hospital in Switzerland, studied a strain of specially-bred mice that are susceptible to narrowing of the arteries. They were fed a high-cholesterol diet to make them develop atherosclerotic plaques.
Adding THC to their diet caused the growth of the obstructions in their arteries to slow down markedly after a period of 11 months. But when the mice were given a chemical that blocked the action of THC, their arteries continued to narrow.
Writing in the journal Nature, the scientists said: "Our results suggest that cannabinoid derivatives with activity at the CB2 receptor may be valuable clinical targets for treating atherosclerosis."
But American critical-care expert Professor Michael Roth, from the University of California at Los Angeles, urged caution when considering cannabis as a heart disease therapy.
"The findings... are striking, but they should not be taken to mean that smoking the drug is beneficial to the heart," he wrote in an accompanying article. "It would be difficult to achieve such specific concentrations in the blood by smoking it."
He said the effects of THC on the brain could trigger a stress response and counteract its benefit to the heart.
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Cannabis chemicals 'cut heart attack risk'
April 07/2005
LInk
But scientists warn that simply smoking cannabis does not offer the same benefit and may actually damage the heart.
THC, or delta-9-tetrahydrocannabinol, is known to affect the brain and make cannabis-users "high". The new research shows that it also has an influence on blood vessels.
A study of mice revealed that the compound blocks the process of inflammation which is largely responsible for the narrowing of arteries.
Inflammation combines with fatty deposits to produce obstructive "plaques", a condition known as atherosclerosis. These can block arteries to the heart, causing angina and heart attacks, or to the brain, leading to strokes.
The scientists, led by Dr Francois Mach from Geneva University Hospital in Switzerland, studied a strain of specially-bred mice that are susceptible to narrowing of the arteries. They were fed a high-cholesterol diet to make them develop atherosclerotic plaques.
Adding THC to their diet caused the growth of the obstructions in their arteries to slow down markedly after a period of 11 months. But when the mice were given a chemical that blocked the action of THC, their arteries continued to narrow.
Writing in the journal Nature, the scientists said: "Our results suggest that cannabinoid derivatives with activity at the CB2 receptor may be valuable clinical targets for treating atherosclerosis."
But American critical-care expert Professor Michael Roth, from the University of California at Los Angeles, urged caution when considering cannabis as a heart disease therapy.
"The findings... are striking, but they should not be taken to mean that smoking the drug is beneficial to the heart," he wrote in an accompanying article. "It would be difficult to achieve such specific concentrations in the blood by smoking it."
He said the effects of THC on the brain could trigger a stress response and counteract its benefit to the heart.
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Cannabis chemicals 'cut heart attack risk'
April 07/2005
LInk
