title: Step response of mouse rod photoreceptors modeled in terms of elemental photic signals.
abstract: The process of light adaptation in rod photoreceptors enables these sensory cells of the retina to remain responsive to photic stimuli over a broad range of light intensity. Recent studies have employed the technique of paired-flash electroretinography to determine properties of phototransduction, and of light and dark adaptation, in rod photoreceptors in the living eye. Building on these studies, we have developed a theoretical model aimed at explaining the rod electrical response to a step of light based on known physiology. The central feature of the model is its description of the macroscopic (i.e., measured) response in terms of a time-evolving, weighted sum of elemental responses determined under dark-adapted and near fully light-adapted conditions. The model yields a time-dependent function that describes the course of desensitization and putatively represents the cumulative dynamics of underlying biochemical processes involved in light adaptation of the rod.
authors.affiliation: Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, College of Medicine, Chicago, IL 60612, USA. gsilva@ucsd.edu
authors.forename: Gabriel A
authors.initials: GA
authors.lastname: Silva
authors.forename: David R
authors.initials: DR
authors.lastname: Pepperberg
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000221:Adaptation, Ocular / Q000502:physiology* / Q000528:radiation effects*; D000222:Adaptation, Physiological / Q000502:physiology / Q000528:radiation effects; D000818:Animals; D003198:Computer Simulation; D003624:Darkness; D004596:Electroretinography / Q000379:methods; D006706:Homeostasis / Q000502:physiology; D008027:Light; D051379:Mice; D008954:Models, Biological; D010775:Photic Stimulation / Q000379:methods*; D015203:Reproducibility of Results; D017948:Retinal Rod Photoreceptor Cells / Q000503:physiopathology*; D012680:Sensitivity and Specificity; D015398:Signal Transduction / Q000502:physiology* / Q000528:radiation effects*