Table 1.

Results of Modulation of the Endocannabinoid System in Murine Models With Inflammatory Bowel Disease

Study	Results
Massa et al20	CB1-/- mice have an increased risk of colitis vs wild mice after induction with DNBS and dextran sulfate sodium. In CB2-/- mouse models, the effect is similar, suggesting that these cannabinoid receptors together maintain intestinal homeostasis.
Engel et al21	Double-knockout mice, CB1-/- and CB2-/-, do not show increased relative susceptibility to TNBS-induced colitis compared with single-knockout models, suggesting additional compensatory mechanisms accounting for a more robust inflammatory response. In FAAH—knockout mice with increased endocannabinoid levels, there is less response to DNBS-induced colitis.
Alhouayek and Muccioli8	Levels of anandamide are increased in the colons of DNBS- and TNBS-rats, whereas levels of 2-arachidonoylglycerol appear unchanged. Expression of FAAH mRNA (precursors to the enzyme involved in degradation of anandamide) has shown to be decreased in inflamed colons; however, this does not seem to correlate with changes in FAAH activity.

CB1, cannabinoid 1 receptor; CB2, cannabinoid 2 receptor; DNBS, dinitrobenzene sulfonic acid; FAAH, fatty acid amide hydrolase; TNBS, trinitrobenzene sulfonic acid.