Table 5

Parameters for the interaction of BNO with [3H]NMS and ACh at m1—m5 muscarinic receptors

SubtypeAssayLog affinityCooperativityn
Unoccupied receptor[3H]NMS-occupied receptor[3H]NMSACh
m1Nonequilibrium3.37  ± 0.083.53  ± 0.101.47  ± 0.103
Equilibrium3.39  ± 0.113.57  ± 0.131.56  ± 0.200.96  ± 0.174
m2Nonequilibrium3.13  ± 0.043.32  ± 0.031.55  ± 0.042
Equilibrium2.68  ± 0.123.25  ± 0.093.75  ± 0.400.43  ± 0.204
m3Nonequilibrium2.79  ± 0.092.82  ± 0.101.06  ± 0.023
Equilibrium2.73  ± 0.162.89  ± 0.155-a 1.16  ± 0.082.60  ± 0.204
m4Nonequilibrium3.68  ± 0.033.67  ± 0.080.98  ± 0.113
Equilibrium3.46  ± 0.113.47  ± 0.065-b 0.91  ± 0.091.42  ± 0.125-c 4
m5Nonequilibrium
Equilibrium2.45  ± 0.072.65  ± 0.051.60  ± 0.080.78  ± 0.172

  • ↵5-a n = 3, log affinity at the [3H]NMS-occupied receptor was fixed at 2.5 in one assay.

  • ↵5-b n = 3, log affinity at the [3H]NMS-occupied receptor was fixed at 3.6 in one assay.

  • ↵5-c Significantly different from 1, p < 0.05, two-tailed t test.