Interaction between cytokines, cannabinoids and the nervous system.

Cytokines play important roles in neuroinflammation and neurodegeneration. The endocannabinoid system (ES) is comprised of the CB1 and CB2 cannabinoid receptors, endogenous ligands, and proteins involved in endocannabinoid synthesis and inactivation. The ES participates in the regulation of immune responses in the nervous system. Activation of the cannabinoid system is associated with therapeutic effects that may be mediated by the down-regulation of cytokine expression. Here we review the findings from studies on the reciprocal regulation of the immune and cannabinoid systems, which is based on functional as well as anatomical connections. We then discuss mechanisms involved in the reciprocal regulation of cytokines and the ES.