Membrane Conductances and Spectral Sensitivities of Pecten Photoreceptors

摘要: The electrical and spectral properties of depolarizing (proximal) hyperpolarizing (distal) photoreceptors in the eye scallop, Pecten irradians, were examined. Both responses are associated with an increase membrane conductance; addition, response is characterized by a secondary decrease conductance at light intensities which inactivate response. can be reversed polarity applied current across cell membrane. has reversal potential approximately +10 mv, whereas estimated for near -70 mv. two have same sensitivity function, agrees Dartnall nomogram rhodospin λmax 500 nm. It suggested that photochemical reactions produce different end products give opposite proximal distal cells, or alternatively, respective membranes to product different.