The Role of Vasopressin in Anxiety and Depression

Abstract

The nonapeptide vasopressin (Avp) is an important player in an animal’s response to stress. As an integral part of the hypothalamic-pituitary-adrenal (HPA) axis, Avp has been identified as a potential contributor to stress-related disorders, such as anxiety and depression, as they are characterized by impairments of the HPA axis. Avp mediates its effects through three receptor subtypes: the Avp 1a receptor (Avpr1a), the Avp 1b receptor (Avpr1b), and the Avp 2 receptor (Avpr2). While the Avpr1a and Avpr1b are expressed in the central nervous system, the Avpr2 appears to be restricted to the periphery. In rodents, the Avpr1b has consistently been implicated in the modulation of anxiety- and depression-related behaviors, and these findings are supported by the human literature. In depressed humans, serum concentrations of Avp are abnormally high and polymorphisms of the Avpr1b are associated with resilience to the development of mood disorders. Moreover, recent data suggests that administration of an Avpr1b antagonist can alleviate symptoms of depression and has shed light on the potential clinical relevance of the Avpergic system to anxiety and depression. In this chapter, we review the recent scientific literature from both animal and human studies regarding the contributions of Avp and its receptors to stress, anxiety, and depression.