CHEMBL5735496

Dopamine D2 Receptor Agonism: Dopamine D2 receptor agonism was measured using a calcium mobilization assay protocol developed by HD Biosciences (China). Briefly, HEK293/G15 cells expressing human D2 receptor were plated at a density of 15000 cells/well in clear-bottomed, Matrigel-coated 384-well plates and grown for 24 hrs at 37° C. in the presence of 5% CO2. The cells were incubated with calcium-sensitive fluorescent dye, Fluo8, for 60-90 minutes at 37° C. in the dark. Test compounds were prepared at 3-fold concentrated solution in 1×HBSS buffer with Ca2+ and Mg2+. Calcium Flux signal was immediately recorded after compounds were added from compound plate to cell plate at FLIPR (Molecular Devices). The fluorescence data were normalized to yield responses for no stimulation (buffer) and full stimulation (1 μM of dopamine) of 0% and 100% stimulation, respectively. Test compound potency (EC50) was estimated by nonlinear regression using the sigmoidal dose-response (variable slope) using Xlfit 4 (IDBS, Guildford, Surrey, UK, model 205).y=(A+((B−A)/(1+((C/x){circumflex over ( )}D))))where y is the normalized ratio measurement for a given concentration of test compound, x is the concentration of test compound, A is the estimated efficacy at infinite compound dilution, and B is the maximal efficacy. C is the EC50 value and D is the Hill slope coefficient.EC50 estimates were obtained from independent experiment and the logarithmic average was calculated.