AVPR1B and Anxiety: With regard to social and emotional behavior, the neuropeptides oxytocin (OXT), vasopressin (AVP) and their receptors (AVPR1A, AVPR1B, and OXTR) gain particular attention [11,12] because the role of OXT and AVP in the mechanisms of establishing and maintaining social interaction, social memory, empathy, prosociality, and anxiety is well recognized [11].