Figure 2.

Cluster properties vs. the concentration of ACh. (top) Example clusters at three different ACh concentrations. (bottom) Between 1 and 100 μM ACh, the probability of being open within a cluster increases and the corrected mean cluster duration (τ_c) decreases. However, the product of these parameters remains nearly constant at ∼300 ms. The mean desensitization rate constant (τ_c P _o)⁻¹ is 3.5 s⁻¹. Each point is the mean of more than two patches, with 5–63 clusters per patch (mean = 27).