title: Sensitization in voltage clamped barnacle photoreceptors.
abstract: 1. The light response of Balanus lateral eye photoreceptor was studied using intracellular recording and voltage clamp techniques. 2. The effect upon the light response of a prior depolarization was studied. Two effects were observed: a transient sensitization which appeared not to involve a change in time course, and a long-lived desensitization which was accompanied by a reduction in response time course. 3., The sensitizing effect of depolarizing prepulses increased monotonically with prepulse duration; it was maximal for pulses to around +20 mV. 4. Sensitization was inhibited by perfusion with salines containing cobaltous ions or with calcium-free saline. 5. It is concluded that while desensitization is an effect upon the transduction mechanism, sensitization is a direct influence of a prior depolarization on the light-activated channels.
mesh_terms: D000818:Animals; D002118:Calcium / Q000037:antagonists & inhibitors / Q000502:physiology; D003035:Cobalt / Q000494:pharmacology; D066298:In Vitro Techniques; D008564:Membrane Potentials; D010775:Photic Stimulation; D010786:Photoreceptor Cells / Q000502:physiology*; D001468:Thoracica / Q000502:physiology*
chemical_list: D003035:Cobalt; D002118:Calcium