Modes are stable. (A; left) Low time-resolution view of αP197A (+αY93A) clusters from a patch having a single AChR. (Right) Corresponding histograms (adult AChR, 30 µM ACh; −100 mV; open is down). For ∼30 min, P_O was homogeneous. (Right, bottom) The slowest shut component (arrow; 162 ± 70 s), which represents recovery from deep desensitization, is similar to the WT value (270 s; Elenes and Auerbach, 2002), indicating that the patch probably had only one AChR. (B) A multichannel patch of the same construct shows P_O modes.