Figure 7.

Hypothesized mechanism to explain experimental observations during repetitive stimulation under normal conditions (left box) and following amytal-induced partial inhibition of electron transport chain (ETC) activity (right box) Sequential processes above the boxes are common to both conditions; divergence occurs as a result of differing extents of acceleration of ETC activity in normal and inhibited mitochondria in response to the Ψ_m depolarization produced by Ca²⁺ influx. This proposed mechanism helps to explain why repetitive nerve stimulation produced greater Ψ_m depolarization and greater elevation of cytosolic [Ca²⁺] in the presence of amytal.