Endometriosis is a chronic inflammatory disease affecting 1 in 9 Australian women, predominantly of reproductive age. The disease is often described as the growth of uterine-like tissue outside of the uterus and the clinical symptoms include chronic severe pelvic pain, painful menstruation, painful intercourse, and infertility. The current treatments are limited and include surgery and hormonal contraceptives which are suggested to be inadequate for pain management and supress fertility, respectively. The neuropeptide S receptor 1 (NPSR1) is centrally and peripherally expressed. Its expression is upregulated in chronic inflammatory diseases including asthma, irritable bowel disease and endometriosis. In mouse models of peritoneal inflammation and endometriosis, NPSR1 antagonism reduces inflammation and abdominal pain, respectively. This highlights the therapeutic potential of the NPSR1 as a drug target for non-hormonal drugs to treat pain associated with endometriosis and other chronic inflammatory diseases. Currently, there are no experimentally determined atomic structures of the NPSR1 which is suggested to be a major contributor to the lack of NPSR1 targeted drugs progressing to clinical studies. Here, we have designed several NPSR1 constructs with amino-terminus (N-terminus) modifications to assess their protein expression using SDS-PAGE and Western Blot. The NPSR1 constructs tagged with FLAG, mini-Gisq and the muscarinic acetylcholine M4 receptor N-terminus (M4NT) show moderate to high expression and will be further assessed in a small-scale FLAG purification assay. Additionally, the functional activity of currently available NPSR1 antagonists will be assessed to allow candidate selection for future in vivo studies of mouse models with pelvic pain. Here, we report that NPSR1 antagonists SHA 68, NCGC84 and MIPS-54170 inhibit neuropeptide S (NPS)-induced calcium mobilisation with pA2 ± SEM values of 7.13 ± 0.12, 7.67 ± 0.07, and 8.21 ± 0.03, respectively. These preliminary experiments will be followed up with protein purification and sample vitrification in order to determine cryogenic electron microscopy (cryo-EM) structures of the NPSR1 in complementation with in depth pharmacology and receptor mutagenesis. Collectively, these experiments may guide the development of new NPSR1 antagonists for the treatment of endometriosis and other inflammatory diseases.