The prolonged hyperpolarizing afterpotential in an invertebrate photoreceptor: wavelength and ionic dependence.
A single electrode voltage clamp was used to examine the prolonged hyperpolarizing afterpotential (PHA) which accompanies photoconversion of a substantial fraction of rhodopsin (lambda max = 500 nM) to metarhodopsin (lambda max = 575 nM) in distal photoreceptor cells in the retina of the bay scallop, Pecten irradians. The PHA appears to result from a persistent light-activated outward K+ current passing through the same channels responsible for the normal receptor potential in these cells.
D000818:Animals; D005074:Evoked Potentials, Visual; D007473:Ion Channels / Q000502:physiology*; D008027:Light; D008974:Mollusca; D010786:Photoreceptor Cells / Q000502:physiology*; D011188:Potassium / Q000378:metabolism; D012243:Rhodopsin / Q000031:analogs & derivatives / Q000502:physiology
D007473:Ion Channels; C013110:metarhodopsins; D012243:Rhodopsin; D011188:Potassium