“The opioid system consists of three receptors, mu, delta, and kappa, which are activated by endogenous opioid peptides (enkephalins, endorphins, and dynorphins).
The endogenous cannabinoid system comprises lipid neuromodulators (endocannabinoids), enzymes for their synthesis and their degradation and two well-characterized receptors, cannabinoid receptors CB1 and CB2.
These systems play a major role in the control of pain as well as in mood regulation, reward processing and the development of addiction.
Both opioid and cannabinoid receptors are coupled to G proteins and are expressed throughout the brain reinforcement circuitry.
A better understanding of opioid-cannabinoid interactions may provide novel strategies for therapies in addicted individuals.”