Dependence of MscS inactivation on the preconditioning saturating pulse at different tensions. (A) Ramp responses of channel population in a patch characterized by the midpoint of 153 mmHg and saturating pressure of 180 mmHg. Responses to the step pulse protocol with the increasing amplitude of a 30-s step (B). (C) Responses of the same patch to pulse-step-pulse stimuli, where the first short pulse opens the entire MscS population, and the pulse at the end reveals the part of the population remaining active in both protocols (arrows). Inactivated fractions of channel population plotted as a function of normalized pressure during the 30-s step (D) are similar regardless of the presence of the first pulse. The data were collected on a single representative patch and were qualitatively reproduced on four separate patches. In D, pressures are normalized to the ramp response midpoint p0.5 (A).
