The prolonged depolarizing afterpotential and its contribution to the understanding of photoreceptor function.

摘要: Comparison of flies bred on vitamine A-poor and A-rich diets show the latter to exhibit, after blue illumination, 1) slight deviation from linear relationship between stimulus intensity receptor sensitivity and, 2) intense illumination phenomenon PDA. Both these effects could result reduced pigment distances in such membranes. Maximum PDA was produced about 20 s with light, following this resistance membrane seen stay low, returning resting value at same rate as decline. The response test flashes, repressed during gradually returned decline PDA, similar way photoreceptor would respond sum two stimuli: flash a decreasing background illumination. Red light immediately abolished white small All experiments corroborate new model (without resorting concept inhibitors) which links photopigments excitation, assumptions for are following: is abnormally high primary quantum absorption by rhodopsin molecules, retarded excitation substance stored form, 3) store built up when production larger than its consumption, 4) time energy necessary regeneration excitatory molecules.