Hypertension, or high blood pressure, afflicts an estimated one in four American adults. The condition puts a strain on the human heart and blood vessels and considerably increases the risk of stroke and heart disease.
The endogenous cannabinoid system plays a role in regulating blood pressure as per emerging research, though its mechanism of action is not well understood. It is being demonstrated by animal studies that anandamide and other endocannabinoids profoundly suppress cardiac contractility in hypertension and may normalize blood pressure, which encourages some experts to speculate that the manipulation of the endocannabinoid system "may offer novel therapeutic approaches in a variety of cardiovascular disorders."
On humans and laboratory animals, the administration of natural cannabinoids has yielded conflicting cardiovascular effects. The vascular response in humans administered cannabis in experimental conditions is generally characterized by a mild increase in heart rate and blood pressure. However, complete tolerance to these effects develops quickly and potential health risks appear to be minimal. In animals, the administration of cannabinoids is usually associated with vasodilation, transient bradycardia and hypotension, besides an inhibition of atherosclerosis (hardening of the arteries) progression. Synthetic cannabinoid administration has also been shown for lowering blood pressure in animals and has not been associated with cardiotoxicity in humans.
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 Steven Karch. 2006. op. cit.
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