Rhodopsin in model membranes: charge displacements in interfacial layers.

A model membrane was developed in which interfacial layers of rhodopsin were reoriented onto one side of a thin Teflon film separating two aqueous compartments. Flashes evoked fast photoelectric signals (1 ms) that originated from capacitative charge displacements of oriented rhodopsin upon bleaching. The photoelectric responses of rhodopsin in the model membrane are compared with the early receptor potential of photoreceptor cells; it is concluded that the signals in both systems originate from the same mechanism.