Inactivation of the cannabinoid receptor CB1 prevents leukocyte infiltration and experimental fibrosis.

Objective: Cannabinoids are derivates of the marijuana component Δ(9) -tetrahydrocannabinol that exert their effects on mesenchymal cells and immune cells via CB1 and CB2 receptors. The aim of the present study was to evaluate the role of CB1 in systemic sclerosis.

Methods: CB1-deficient (CB1(-/-) ) mice and wild-type littermates (CB1(+/+) mice) were injected with bleomycin.