The Ready-to-Assay CB1 Cannabinoid Receptor Frozen Cells are a simple, thaw-and-assay cell format for use in studying drug candidates (small molecules or biologics) targeting GPCRs. This assay assesses ligand (e.g. cannabinoids, CP 55,940) based activation of CNR1 GPCR activity via detection of increasing levels of intracellular calcium. The included cell line overexpresses CNR1 alongside endogenous high levels of a promiscuous G-protein, coupling the receptor to the calcium signaling pathway. Upon activation of CNR1, the resulting calcium activity can be fluorescently assayed. Ready-to-assay kits consist of two vials of the stably modified clonal cell line in a convenient thaw-and-use format. For detailed product information, User manual and datasheet, visit www.discoverx.com/products-applications/frozen-cells.