当前位置： SCI文献检索 > JOURNAL OF BIOLOGICAL RHYTHMS期刊下所有文献 > A "melanopic" spectral efficiency function predicts the sensitivity of melanopsin photoreceptors to polychromatic lights.

A "melanopic" spectral efficiency function predicts the sensitivity of melanopsin photoreceptors to polychromatic lights.

Abstract：

:Photoreception in the mammalian retina is not restricted to rods and cones but extends to a small number of intrinsically photosensitive retinal ganglion cells expressing the photopigment melanopsin. These mRGCs are especially important contributors to circadian entrainment, the pupil light reflex, and other so-called nonimage-forming (NIF) responses. The spectral sensitivity of melanopsin phototransduction has been addressed in several species by comparing responses to a range of monochromatic stimuli. The resultant action spectra match the predicted profile of an opsin:vitamin A-based photopigment (nomogram) with a peak sensitivity (λ(max)) around 480 nm. It would be most useful to be able to use this spectral sensitivity function to predict melanopsin's sensitivity to broad-spectrum, including "white," lights. However, evidence that melanopsin is a bistable pigment with an intrinsic light-dependent bleach recovery mechanism raises the possibility of a more complex relationship between spectral quality and photoreceptor response. Here, we set out to empirically determine whether simply weighting optical power at each wavelength according to the 480-nm nomogram and integrating across the spectrum could predict melanopsin sensitivity to a variety of polychromatic stimuli. We show that pupillomotor and circadian responses of mice relying solely on melanopsin for their photosensitivity (rd/rd cl) can indeed be accurately predicted using this methodology. Our data therefore suggest that the 480-nm nomogram may be employed as the basis for a new photometric measure of light intensity (which we term "melanopic") relevant for melanopsin photoreception. They further show that measuring light in these terms predicts the melanopsin response to light of divergent spectral composition much more reliably than other methods for quantifying irradiance or illuminance currently in widespread use.

journal_name

J Biol Rhythms

journal_title

Journal of biological rhythms

authors

Enezi Ja,Revell V,Brown T,Wynne J,Schlangen L,Lucas R

doi

10.1177/0748730411409719

subject

Has Abstract

pub_date

2011-08-01 00:00:00

pages

314-23

issue

eissn

0748-7304

issn

1552-4531

pii

26/4/314

journal_volume

pub_type

杂志文章

在线工具

A "melanopic" spectral efficiency function predicts the sensitivity of melanopsin photoreceptors to polychromatic lights.