D4 Dopamine Receptor Assay from Innoprot allows the measurement of DRD4 receptor activation by Adenylate cyclase inhibition. We assay test-compounds analyzing the G-Protein signalling pathway by Gi/o activation, which involves DRD4 receptor activation. When an agonist binds to DRD4, it activates the Gi/o protein which; in turn, triggers a cellular response mediated by cAMP via adenylate cyclase inhibition. This leads to an increase of fluorescence intensity of cAMP Nomad biosensor. So, the activity can be easily quantified on living cells in a dose-response manner by fluorescence emission in a microplate reader.