[Slow P III component of the electroretinogram resulting from the interaction of photoreceptors and cells of Müller in the retina].

Simultaneously recorded slow PIII (sPIII) and the late receptor potential of the frog isolated aspartate-treated retina were studied under different intensity and duration of light stimuli. The earlier suggested model of the sPIII generation in Müller's cells showed that the sPIII kinetic had to be the same as the light photo-receptor-induced decrease in the extracellular potassium ions concentration. There were some differences between the real sPIII time-course and the theoretical one within the photopic range that were, probably, due to infringement of interrelationships proposed by Matsuura et al. for potassium fluxes through the photoreceptor membrane.