Ligand for the G-protein coupled receptor ntr-1 (PubMed:23112336, PubMed:23112335). Plays a role in gustatory associative learning (PubMed:23112336). Also plays a role in male mating behavior (PubMed:23112335). Detected in thermosensory AFD neurons, neurosecretory NSM cells, AVK interneurons, pharyngeal neuron M5, and the mechanosensory DVA neuron (PubMed:23112336, PubMed:23112335). Detected in male-specific CP motor neurons (PubMed:23112335). Viable and fertile (PubMed:23112336). Gustatory associative learning in response to salt cues is disrupted (PubMed:23112336). Males have reduced reproductive success, due to a range of aberrant mating behaviors (PubMed:23112335). Belongs to the vasopressin/oxytocin family.