Delta opioid receptor: breakthrough target for novel mood stabilizers

Abstract

Psychological stress is a major cause of mental disorders such as major depressive disorder and anxiety disorder. Although an increasing number of the patients is one of the most serious social issues worldwide, it is still unclear how stress provokes these disorders. We have proposed that delta opioid receptor (DOP) is an attractive target for novel antidepressants and anxiolytics due to its potential for rapid action with minimal adverse effects. We have also demonstrated that DOP agonists are potential drugs for post-traumatic stress disorders. Moreover, we found that activation of DOPs in the mouse brain alleviated its irritable bowel syndrome-like symptoms which is closely related to emotional stress. It is noteworthy that we recently reported that DOP agonists produced antidepressant-like effects and anti-stress effects in an animal model of depression through anti-inflammatory actions in the hippocampus, suggesting that DOP agonists has not only therapeutic effects but also prophylactic effects on the stress-induced pathophysiological changes. In this symposium, we introduce the latest information and discuss the potential of DOP agonists as novel mood stabilizers.