Delta-type opioid receptor (OPRD1) (OPRD1)

The Delta-type opioid receptor (OPRD1) is a member of the G protein-coupled receptor family that plays a critical role in the modulation of pain, mood, and reward pathways [5, 11]. It is primarily activated by endogenous enkephalins and is widely distributed throughout the central nervous system, particularly in the cortex, striatum, and limbic system [2, 5]. OPRD1 is a significant therapeutic target for the treatment of chronic pain, emotional disorders like depression and anxiety, and substance use disorders, including alcoholism and opioid addiction [6, 9]. Unlike the Mu-opioid receptor, activation of the Delta receptor is less associated with respiratory depression and physical dependence, making it an attractive target for novel analgesics [4, 9]. Drugs like naltrexone act as non-selective antagonists at this receptor, blocking the reinforcing effects of exogenous opioids and alcohol by preventing the activation of downstream signaling pathways [10, 15]. Genetic variations in the OPRD1 gene, such as specific single nucleotide polymorphisms, are associated with individual differences in pain perception and susceptibility to drug dependence [1, 14]. Furthermore, the receptor is involved in neuroimmunomodulation, influencing the activity of immune cells and inflammatory responses [4, 16].

Other names

Delta opioid receptorDORDOR-1OPRDOpioid receptor delta 1

Naltrexone acts as a competitive antagonist at the Delta-type opioid receptor (OPRD1), as well as the Mu and Kappa opioid receptors, thereby blocking the binding of endogenous and exogenous opioids to prevent their rewarding and physiological effects [10, 15].