Figure 3.

Potency, selectivity, and binding affinity of VU6013720, VU6021302, and VU6021625. Potencies were determined by adding a concentration–response curve of M₄ antagonist followed by an EC₈₀ of acetylcholine in human, rat, or mouse M₄-expressing CHO cells. (A–C) VU6013720, VU6021302, and VU6021625 induced a concentration-dependent inhibition of the release of calcium. The selectivity of these M₄ antagonists was evaluated by adding a concentration–response curve of compound followed by an EC₈₀ of acetylcholine in M₁, M₂, M₃, M₄, or M₅ expressing CHO cells. Competition binding assay of this series of compounds with [³H]-NMS in rat (G) or mouse (H) M₄-expressing CHO cell membranes. Data represent the mean ± SEM of 3 independent experiments performed in duplicate.