Oxytocin is an evolutionary conserved peptide hormone that is synthesized and released from the hypothalamus for reproduction and maternal behavior. Recent studies have tagged oxytocin as a “trust” hormone, that promises to improve social deficits in various mental disorders, such as autism. Despite the enthusiasm for oxytocin, the efficacy of oxytocin in improving human social behaviors has been contradictory. Such inconsistencies are likely due to our poor understanding of complexity of oxytocin action and the behavioral measures that have been used in clinical trials. A better understanding of the mechanisms of oxytocin is needed to apply the therapeutic potential of this neuropeptide. Recently we showed that oxytocin enables mice to recognize infant distress calls through the auditory system that enhanced maternal pup retrieval thru oxytocin receptors. The hypothesis of this application is that the identification of downstream targets of oxytocin receptors will provide a means of analyzing oxytocin signaling across molecular, physiological, systems and behavioral levels. We have developed new assays and antibodies to follow the action of the oxytocin receptor, a G protein-coupled receptor. The aim of this project is to understand how the many actions of oxytocin are translated from its receptor signal transduction pathways. An initial goal will be to follow the downstream proteins that mediate the functions of oxytocin. This includes G proteins, calcium- dependent proteins, scaffold proteins like gephyrin and receptor tyrosine kinases, such as the BDNF TrkB receptor.