FIGURE 3.

Influence of rWTX on rate of orthosteric antagonist [³H]NMS dissociation at M1, M2, and M3 mAChRs. A–C, time course of dissociation of [³H]NMS in the presence and absence of 10 μm rWTX was determined as described under “Experimental Procedures.” Specific binding of [³H]NMS was calculated as a difference between total and nonspecific binding measured in the same experiment and is expressed in percent of initial binding (ordinate). Results are given as means ± S.E. (n = 3). D, 10 μm rWTX decreased [³H]NMS dissociation rate constants (K_off, min⁻¹) from 0.118 ± 0.005 to 0.076 ± 0.003, from 0.81 ± 0.04 to 0.63 ± 0.03, and from 0.074 ± 0.002 to 0.065 ± 0.002 at the M1, M2, and M3 subtypes, respectively. Data designated as *, p < 0.05, and **, p < 0.01, are significantly different from control by two-tailed t test.