CB1 is the main cannabinoid receptor in the brain but is also found in other tissues. CB1 is a G protein-coupled receptor which inhibits adenylyl cyclase and consequently reduces cAMP upon activation. This in turn regulates many second messenger pathways. 

Cav1 is a family of calcium channels of the L-type that are involved in many basic signalling processes in brain and muscle. Cav1's are not classic cannabinoid receptors but their activity is modulated by cannabinoids.