Run-up of rapidly adapting mechanically activated currents in DRG neurons under the conventional whole-cell patch-clamp configuration. A) Image shows a DRG neuron with a patch-clamp recording electrode and a mechanical stimulation probe. B) Sample traces show the rapidly adapting mechanically activated currents (RA) evoked by a 7-μm membrane displacement. Left panel is the RA current at the initial time (▲ indicated) and right panel the RA current 30 min (▲ indicated) after establishing the whole-cell mode. Membrane displacement is indicated on the top of each trace. The traces also include membrane tests continually conducted at the interval of 100 ms by voltage steps of 5 mV. C) Traces are from B at expanded scales. Left, two superimposed traces of RA currents, one at the initial time (solid line) and the other 30 min (orange line) after establishing the whole-cell mode. Right, two superimposed traces of the membrane tests at the initial time (solid line) and 30 min (orange line) after establishing the whole-cell mode. D) Summary data of the time course of RA current run-up (n = 40–63 cells). The line in the graph shows linear regression for the mean values of RA currents at different time points. The slope and the coefficient of determination (r2) of the linear regression are given in the graph. The P value indicates how significant is the slop (i.e. the trend of change) different from zero (i.e. no change). The number on the top of each symbol indicates the number of cells at each time point. *P < 0.05, **P < 0.01, ***P < 0.001, compared to the initial RA current.