Abstract: The endocannabinoid system is a complex physiological system, consisting of endocannabinoid and the enzymes involved in their biosynthesis and degradation as well as the cannabinoid receptors. Recent researches have confirmed the relationship between endocannabinoid system and bone metabolism. Studies show that CB-1 and CB-2 receptors, two of the most important receptors, are found in bone cells and have different effects on bone metabolism. In addition, other receptors such as TPRV1, GPR55, GPR119, and TPRV4 are involved in bone metabolism, too. Anandamide and 2-arachidonoylglycerol, two typical endocannabinoids, and their agonists and antagonist regulate osteoblast and osteoclast's differentiation and proliferation as well as bone remodeling through the mediation of cannabinoid receptors. It is thus clear that the endocannabinoid system is a potential target for future treatment to increase bone regeneration. Prospective studies on the relationship between the endocannabinoid system and bone metabolism are needed.

Key words: cannabinoids, cannabinoid receptors, endocannabinoids, endocannabinoid system, bone metabolism