Fig. 7.

Characteristics of the outward currents in isolated human gastric corpus smooth muscle cells. A: a representative trace showed outward currents during step depolarization up to +70 mV in 10 mV increment from a holding potential of −80 mV. Cells were exposed to Ca²⁺-containing physiological solution (CaPSS) externally and dialyzed with K⁺-rich solution (100 nM intracellular Ca²⁺ concentration) internally. B: TEA (1 mM) decreased outward currents and remained the delayed rectifying K⁺ currents (TEA-resistant). C: subtracted currents from A to B showed TEA-sensitive currents (mainly BK). D: summarized current-voltage (I–V) relationship of the net outward (control, ○) and BK (TEA-sensitive, ●) and delayed rectifying K⁺ (TEA-resistant, ◇) currents. E: voltage-dependent activation from TEA-resistant (●) and TEA-sensitive (○) currents. Boltzmann equation was applied to calculate half activation in normalized with maximal conductance (G/G_max).