NPW is a 165 amino acid secreted protein that is cleaved into two chains: neuropeptide W-23 (also designated NPW23 or L8) and neuropeptide W-30 (also known as NPW30 or L8C). Both NPW neuropeptides activate G-protein coupled receptors in the central nervous system to enhance cortisol secretion. Highly expressed in lymphoblastic leukemia, colorectal adenocarcinoma, fetal kidney, trachea and substantia nigra, NPW is also found at low levels in placenta, ovary, testis and uterus. NPW functions in organization of neuroendocrine signals and is also thought to enhance food and water intake as well as stress responses. The gene encoding NPW maps to human chromosome 16p13.3.