TABLE 1

Comparisons of ligand affinity/potency at hM3-R and hM3-RASSL constructs

All experiments were performed on stable Flp-In T-REx 293 cell lines able to express the noted construct upon addition of doxycycline. Data shown are the mean ± S.E.M. of two to four independent experiments performed in triplicate (see text and figure legends for full details). Bmax values were obtained from cells induced to express the receptors with a maximally effective concentration of doxycycline.

KD [3H]QNBBmaxKi AtropinepEC50
FRET[Ca2+]pERK1/2Internalization
CchCNOCchCNOAchCchCNOAchCchCNO
pmol/mgnM
hM3-R FlAsH75 ± 28 pM6.5 ± 0.660.74 ± 0.14.9 ± 0.2>3.07.2 ± 0.047.8 ± 0.3N.D.N.A.
hM3-RASSL FlAsH7.9 ± 2.2 nM3.5 ± 0.8947 ± 17>3.05.1 ± 0.47.6 ± 0.1N.D.N.A.
VSV-SNAP-hM3-R35 ± 9 pM12.6 ± 1.20.74 ± 0.2N.A.7.5 ± 0.46.9 ± 0.1>4.07.9 ± 0.34.8 ± 0.16
VSV-SNAP-hM3-RASSL1.4 ± 0.04 nM2.6 ± 01323 ± 1.4N.A.7.7 ± 0.6>4.07.6 ± 0.46.2 ± 0.15
  • Ach, acetylcholine; Cch, carbachol; CNO, clozapine N-oxide, N.D., not determined; N.A., not applicable.