The presence of strongly pronounced metabolic dependence of cooling-induced action potentials (APs) in excitable cells of pumpkin stem was shown using NaN3, DCCD, and IAA. This dependence might be connected with participation of the plasma-membrane ATP-dependent pump in the excitation process. The decrease of extracellular Ca2+ concentration had as strong depressive effect on the AP as that of the inhibition of metabolism. It has been supposed that the calcium signal is important coupling factor between the AP generation and the metabolism of excitable cells.