Vasopressin (AVP) and oxytocin (OT) are two chemically similar neurohypophyseal neuropeptides which could be involved in mood disorders. Those two sister neuropeptides might be considered as ago-antagonist hormones. They act as neuromodulators of the stress response. AVP is known as an ACTH stimulating factor synergistic to CRH while OT could act as an antagonist of AVP on ACTH secretion. AVP seems to play an important role in the pathophysiology of major depression. Evidence suggests a role for OT as an endogenous antidepressant/anxiolytic hormone. OT release is also an important aspect of the pharmacological action of SSRIs. In addition, their receptors are of growing interest for psychiatric research. A selective AVP V1b receptor, SSR1419415, has been characterized and is endowed with anxiolytic- an and antidepressant-like properties. This paper proposes an overview of neurohypophyseal hormones in major depression.