M. Dorlochter et al., RECEPTOR CURRENT OSCILLATIONS EVOKED BY LOCAL ILLUMINATION IN LIMULUSVENTRAL NERVE PHOTORECEPTORS, Journal of photochemistry and photobiology.B, Biology, 35(1-2), 1996, pp. 115-122
Light flashes to spots on ventral photoreceptors induced complex curre
nt bursts or oscillations. The number of peaks in a burst was not corr
elated with the number of effective photons. Intervals between peaks w
ere constant in each cell. Net charge fluxes during bursts were larger
than the charge flux during a single bump multiplied by the number of
peaks. The number of peaks, current-time-integrals, and kinetics of b
ursts evoked either by light spots or by illumination of the same enti
re cell were similar. Occasionally, bursts appeared at stimulus intens
ities corresponding with only 1-2 effective photons. At higher intensi
ties they occurred more frequently, and the average burst-evoking inte
nsity corresponded with 6 effective photons. We conclude that a single
photoisomerization can induce a current burst due to a local oscillat
ory process.