Drug addiction,also referred to as drug dependence or substance use disorder,is a chronic and recurrent brain disease.Its main characteristics are compulsive drug-seeking behavior,continued use of drugs,and a loss of control over intake.Prolonged use of addictive substances can result in both physiological and psychological dependence.When usage is ceased,individuals may experience intense discomfort,including anxiety,insomnia,nausea,vomiting,and a strong craving for the substances.Drug dependence is classified into two types:physical dependence and psychological dependence.Physical dependence describes a pathological state of adaptation that results from the repeated use of addictive substances,leading to severe withdrawal syndrome upon cessation.Psychological dependence involves a mental craving for addictive substances,which is needed to experience the specific euphoria that follows consumption.Regular or continuous use is required to sustain these euphoric effects.The mechanisms of addiction are complex and influenced by genetic,environmental,and various other factors.They involve higher-level neurological activities,such as memory,reward,and decision-making.Currently,effective treatment methods for drug addiction are insufficient.Due to the complexity of drug addiction,laboratory animal research is essential.Using animal behavioral models to simulate human drug addiction can enhance our understanding of the mechanisms of addiction.This research offers a comprehensive overview of various animal experimental models that explore both physical and psychological dependence.It includes detailed descriptions of the methods and procedures used to assess physical dependence,behavioral sensitization,conditioned place preference,drug discrimination,and self-administration experiments.Additionally,the characteristics of each experimental model are compared,and the relevance of these models is discussed,aiming to provide support for the research on addiction mechanisms and the development of therapeutic methods.

Drug addiction,also referred to as drug dependence or substance use disorder,is a chronic and recurrent brain disease.Its main characteristics are compulsive drug-seeking behavior,continued use of drugs,and a loss of control over intake.Prolonged use of addictive substances can result in both physiological and psychological dependence.When usage is ceased,individuals may experience intense discomfort,including anxiety,insomnia,nausea,vomiting,and a strong craving for the substances.Drug dependence is classified into two types:physical dependence and psychological dependence.Physical dependence describes a pathological state of adaptation that results from the repeated use of addictive substances,leading to severe withdrawal syndrome upon cessation.Psychological dependence involves a mental craving for addictive substances,which is needed to experience the specific euphoria that follows consumption.Regular or continuous use is required to sustain these euphoric effects.The mechanisms of addiction are complex and influenced by genetic,environmental,and various other factors.They involve higher-level neurological activities,such as memory,reward,and decision-making.Currently,effective treatment methods for drug addiction are insufficient.Due to the complexity of drug addiction,laboratory animal research is essential.Using animal behavioral models to simulate human drug addiction can enhance our understanding of the mechanisms of addiction.This research offers a comprehensive overview of various animal experimental models that explore both physical and psychological dependence.It includes detailed descriptions of the methods and procedures used to assess physical dependence,behavioral sensitization,conditioned place preference,drug discrimination,and self-administration experiments.Additionally,the characteristics of each experimental model are compared,and the relevance of these models is discussed,aiming to provide support for the research on addiction mechanisms and the development of therapeutic methods.

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.

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.