The number of people living with obesity has tripled worldwide since 1975 with serious implications for public health. As obesity is a consequence of food intake exceeding energy expenditure, efforts are being made to better understand the neuroendocrine mechanisms governing food intake. Peptide hormones secreted from the gastrointestinal tract modulate food intake via interactions with the peripheral and central nervous systems. My research focuses on the gut peptide hormone insulin-like peptide 5 (INSL5), previously shown to increase food intake, and its receptor relaxin/insulin-like family peptide receptor 4 (RXFP4) in the central nervous system. Through this research I aim to elucidate the role of central INSL5-RXFP4 action in the control of food intake and food preference. Expanding understanding of INSL5-RXFP4 action is essential due to the identification of this ligand-receptor pair as a potential therapeutic target for obesity and other food intake-related disorders.