Studies on microplasmodia of Physarum polycephalum V: electrical activity of different types of microplasmodia and macroplasmodia.

Results obtained by three different electrophysiological methods delivered mainly oscillating potentials (independently of the type of organization of Physarum polycephalum) with an average period length of 1 min 21 sec. This value is in good statistical agreement with corresponding data for the periodical oscillation of the shuttle streaming (1 min 47 sec) and coincides also with the radial tensiometric contractile activity (1 min 34 sec). The investigation favours the hypothesis that ion fluxes across the cell membrane and perhaps between intracellular compartments may act as a trigger mechanism for a still unknown oscillator-system which controls cell movement phenomena in the acellular slime molds.