Fig. 7.
VU0029767 potentiated responses of a mutant M1 receptor with greatly reduced affinity for ACh, whereas VU0090157 did not. DMSO vehicle, 30 μM VU0029767 (A), or VU0090157 (C) was preapplied to M1Y381A cells before the addition of increasing concentrations of ACh. Compound concentration-response curves of VU0029767 (B) and VU0090157 (D) were generated in the presence of an EC20 concentration of acetylcholine (1.4 nM for WT and 7.5 μM for the M1Y381A receptor) in a calcium assay using cells expressing either the WT M1 receptor (▪) or the M1Y381A receptor (□). Data represent the mean ± S.E.M. of three independent experiments performed in quadruplicate.