Introduction Similarly to the µ opioid receptor, kappa opioid receptor (KOR), is present either in the central nervous system and peripherally. In the last years several molecules, able to interact with KOR, have been the focus of basic research for their therapeutic potential in the field of chronic pain, as well as in depression, autoimmune disorders and neurological diseases.
Topic The role of KOR system and the consequent clinical effects derived by its activation or inhibition are discussed. Their potential therapeutic utilization in conditions of stress and drug relapse, besides chronic pain, is here presented, including the possible use of KOR-agonists in drug addiction. Moreover, the potential role of KOR-antagonists, KOR agonist-antagonists, and peripheral KOR agonists is proposed.
Conclusion. Other than pain, KORs have a role in regulating reward and mood. Due to its location, KORs seems to mediate interactions between psychiatric disorders, addiction, and depression. Experimental studies in animal models have identified brain mechanisms that may contribute to clarify specific pathophysiological processes.