Communicating junctions of the human sensory retina. A freeze-fracture study.

Using the freeze-fracture technique communicating junctions could be identified between the cells of the adult human sensory retina. Communicating junctions with particles arranged in linear or circular rows as well as in small aggregates were found between adjacent photoreceptor endings. Communicating junctions with particles forming plaques were localized in the inner plexiform layer. They were isolated between unidentified cell processes or lay close to active sites of chemical synapses, thus suggesting the occurrence of "mixed" (chemical and electrical) synapses in this layer. Furthermore, communicating junctions were detected between portions of Müller's cells.