Effects of xanomeline pretreatment on [3H]NMS saturation binding parameters in CHO hM1, rM1, and mutant123 cells.

Cells were pretreated with 300 nM or 3 µM xanomeline for 1 h or 24 h at 37°C followed by washing and immediate use in the binding assay or for 1 h followed by washing and further incubation in the absence of free xanomeline for 23 h. Cells were then incubated with increasing concentrations of [3H]NMS at 37°C for 1 h. Parameters derived from computer-assisted non-linear regression analysis as described in Methods are presented as mean ± S.E.M. of three to ten experiments conducted in triplicate.aEquilibrium dissociation constant for [3H]NMS binding.bMaximal cell-surface receptor density (dpm/100,000 cells).cControl, naïve cells were incubated with radioligand.dNot measured.*ANOVA followed by Dunnett’s post-test detected a significant difference (pD or Bmax between the pretreated groups compared with vehicle control.