title: Additivity in murine circadian phototransduction.
abstract: Additivity in the circadian phototransduction system of the mouse has not been tested directly. Because of this, accurate prediction of circadian phase shifts elicited by polychromatic light stimuli cannot be derived from the results of studies using monochromatic light stimuli. This limitation also makes it impossible to deduce the relative contributions of the photoreceptive mechanisms (rods, cones and melanopsin-containing retinal ganglion cells) underlying circadian phototransduction in the mouse. Using nearly monochromatic light stimuli of different spectral composition, and combinations thereof, we demonstrated that murine circadian phototransduction exhibits additivity. Based on the locomotor activity phase shifts elicited by these stimuli, we developed the first quantitative assessment of the relative contributions of conventional and novel photoreceptive mechanisms for circadian functioning in the mouse.
authors.affiliation: Lighting Research Center, Rensselaer Polytechnic Institute, Troy, NY 12180, USA. bulloj@rpi.edu
authors.forename: John D
authors.initials: JD
authors.lastname: Bullough
authors.forename: Mariana G
authors.initials: MG
authors.lastname: Figueiro
authors.forename: Bernard P
authors.initials: BP
authors.lastname: Possidente
authors.forename: Robert H
authors.initials: RH
authors.lastname: Parsons
authors.forename: Mark S
authors.initials: MS
authors.lastname: Rea
mesh_terms: D000818:Animals; D002940:Circadian Rhythm / Q000502:physiology*; D008027:Light; D055537:Light Signal Transduction / Q000502:physiology*; D008124:Locomotion / Q000528:radiation effects; D008297:Male; D051379:Mice / Q000502:physiology*; D008810:Mice, Inbred C57BL; D010775:Photic Stimulation; D020419:Photoreceptor Cells, Vertebrate / Q000502:physiology*