title: Ionic basis of the photoresponse of Aplysia giant neuron: K +  permeability increase.
abstract: The giant neuron of the Aplysia abdominal ganglion hyperpolarizes during illumination. The light-initiated potential change is associated with an increase of membrane conductance. It reverses sign at the potassium equilibrium potential (about -83 millivolts), which was determined from direct measurements of internal potassium activity. The membrane hyperpolarization is produced entirely by a light-induced increase in potassium permeability.
mesh_terms: D000818:Animals; D002463:Cell Membrane Permeability; D008027:Light; D008564:Membrane Potentials; D008974:Mollusca; D009474:Neurons / Q000378:metabolism / Q000502:physiology* / Q000528:radiation effects; D010777:Photochemistry; D010786:Photoreceptor Cells / Q000502:physiology*; D011188:Potassium / Q000378:metabolism*; D011830:Radiation Effects
chemical_list: D011188:Potassium