Addiction is gaining recognition as a leading cause of death, morbility and lost productivity. The urgent clinical and social need to do something about addiction promotes the development of addciton research. This paper reviews the main advances in this area in the latest thirty years, ranging from the initial targets of the major drugs of abuse, to the cAMP pathway in opiate tolerence and dependence and molecular and cellular mechanisms of addiction in VTA-NAc pathway.

G-protein coupled receptors(GPCRs)belong to the biggest subfamily of transmembran receptors.Recently,more and more research has been suggested that the dimerization of GPCRs may regulate the physiological and pharmacological activity.With the development of biochemistry technology and molecular biology,a great progress has been achieved in the field of the dimerization of GPCRs.This article will generally demonstrate that the vital roles of the homodimerization and heterdimerization.

Drug dependence has been a hot topic in neuroscience research due to its complicated pathogenesis. Recently, huge scientific efforts have been continuously put into understanding the association between drug dependence and polymorphism in ATP-binding cassette subfamily B member 1 transporter ( ABCB1 ) gene, especially a mutation in exon 26 at position 3435 (3435C>T). This article reviews the relationship between opioid dependence and analgesic tolerance and ABCB1 gene pol-ymorphism, which will shed light on the underlying mechanisms of drug dependence and optimal MMT programs for individuals.

Opioid analgesics are potent pain-killer and are widely used in clinical practice.Opioid receptors are classified into μ,δ,κ subtypes.Most of the currently available opioid analgesics are μ opioid receptor agonists, but they cause undesired side effects such as physical dependence, respiratory depression and constipation and so on.The antalgic activity of δ receptor agonist is weaker than that of μ agonist, but it can modulate the activity of μ receptor and prevent its addiction. Therefore, discovering and designing compounds with μ/δ dual action is a new way for finding analgesics with low toxicity and less side effects.This review summarizes the development of compound with dual μ/δ activities and provides a new strategy for designing analgesics with low toxicity and less side effects.