Cannabis is widely used for treating a number of gastrointestinal ailments, but its use is associated with several adverse effects, particularly when the route of administration is via smoking. In the present study, we tested the effects (in rats) of a simple extract of
medicinal cannabis (called "MFF") for its ability to promote resolution of
colitis, to prevent gastric damage induced by
naproxen, and to reduce gastric distention-induced
visceral pain. Intracolonic, but not
oral administration of MFF dose-dependently reduced the severity of
hapten-induced
colitis, an effect not reduced by pretreatment with antagonists of CB1 or CB2 receptors. Significant improvement of symptoms (
diarrhea,
weight loss) and healing of ulcerated tissue was evident with MFF treatment at doses that did not produce detectable urinary levels of 9-Δ-tetrahydrocannabinol (
THC). MFF increased colonic
hydrogen sulfide synthesis in healthy rats, but not in rats with
colitis, and had no effect on colonic
prostaglandin E2 synthesis. Orally, but not systemically administered MFF dose-dependently reduced the severity of
naproxen-induced gastric damage, and a CB1 antagonist reversed this effect. MFF prevented gastric distention-induced
visceral pain via a CB2-dependent mechanism. These results demonstrate that a simple extract of
medicinal cannabis can significantly enhance resolution of
inflammation and injury, as well as prevent injury, in the gastrointestinal tract. Interestingly, different
cannabinoid receptors were involved in some of the effects. MFF may serve as the basis for a simple preparation of cannabis that would produce beneficial effects in the GI tract with reduced systemic toxicity.