Endocannabinoids and addiction memory: Relevance to Methamphetamine/Morphine Abuse

The endocannabinoid system (ECS), including cannabinoid receptors and their endogenous lipid ligands, has stimulated the growth of numerous lines of studies investigating the modulatory role of the ECS in drug-induced brain malfunctions. These types of researches are more facilitated by the daily production of cannabinoid receptor agonists and antagonists, and the number of such drugs is growing rapidly. On the other hand, morphine and methamphetamine (METH) have long been known as addictive drugs and cause many mental problems, including memory impairment. Lines of evidence yet have shown that the ECS regulates METH/morphine-induced memory impairment. In this regard, among the neurotransmitters, glutamate and dopamine seem to play a critical role in association with the ECS to heal the drug-induced memory damages. Also, the amygdala, hippocampus, and prefrontal cortex are three important brain regions that participate in both drug addiction and memory task processes, and endocannabinoid neurotransmission have been investigated. This review aims to summarize the role of ECS in the modulation of METH/morphine-induced memory impairments.