Photoreceptor ion channels reconstituted in bilayer lipid membranes

Ion channel molecules in octopus photoreceptor cell membranes were reconstituted in bilayer lipid membranes (BLMs) prepared by the modified monolayer-dipping method. Many kinds of single-channel currents (8-500 pS) were recorded in a BLM that contained a microvillus membrane preparation purified by sucrose density gradient centrifugation. In membranes obtained by a novel filter paper method, only the activity of a low conductance ion channel (10-30 pS) was obtained. It is believed that this may by the ion channel that operates as an electric signal generation in the process of transmitting photo-information in the visual cell