cAMP is a key second messenger involved extensively in cellular signal transduction pathways associated with the majority of G-protein coupled receptors (GPCRs). The activation of these GPCRs by neurotransmitters, lipids, nucleotides, peptides and hormones results in the activation or the inhibition of plasma membrane-bound adenylate cyclase through heterotrimeric G-proteins. The cAMP assay is the first in its class in providing real-time information on intracellular cAMP changes in a high-throughput format without a cell lysis step. The assay works with GPCR-CNG cell lines provided by ChanTest that contain a proprietary exogenous Cyclic Nucleotide-Gated (CNG) channel. The channel is activated by elevated intracellular levels of cAMP, resulting in ion flux (often detectable by calcium-responsive dyes) and cell membrane depolarization (which can be detected with a fluorescent membrane potential (MP) dye).

The Membrane Potential Dye Bulk Kit allows both end-point and kinetic measurement of intracellular cAMP changes with a FLIPR, or a fluorescence microplate reader. It is a simple homogenous assay involving only dye and compound addition steps, allowing easy implementation in a high-throughput environment.