[Changes in the distribution of synaptic vesicles in cone endings following electrical stimulation of the retina]

The conditions were found (hypoxic state of the retina) under which exhausture of the transmitter in presynaptic endings of photoreceptors may be supposed from a decrease in responses of horizontal cells to electric stimulation of the retina. Under these conditions the electric stimulation is accompanied by a decrease in the number of small synaptic vesicles near the presynaptic membranes in cones. However, there are no reliable changes in the total number of vesicles in cone endings.