Fig. 4. Dissociation of [3H]BTX from mouse brain synaptoneurosomes. After incubation of [3H]BTX with synaptoneurosomes for 50 min to achieve equilibrium, the dissociation was initiated by adding either 0.25 mm veratridine in the absence (•) or presence of cOA (▪, 100 μm; or ▴, 200 μm). Binding of [3H]BTX was then measured at the times indicated. Data points represent mean values of four independent experiments.