Diminished Pupillary Light Reflex at High Irradiances in Melanopsin-Knockout Mice

@article{Lucas2003DiminishedPL,
  title={Diminished Pupillary Light Reflex at High Irradiances in Melanopsin-Knockout Mice},
  author={Robert James Lucas and Samer Hattar and M. Takao and David M. Berson and Russell G. Foster and King-Wai Yau},
  journal={Science},
  year={2003},
  volume={299},
  pages={245 - 247}
}
In the mammalian retina, a small subset of retinal ganglion cells (RGCs) are intrinsically photosensitive, express the opsin-like protein melanopsin, and project to brain nuclei involved in non–image-forming visual functions such as pupillary light reflex and circadian photoentrainment. We report that in mice with the melanopsin gene ablated, RGCs retrograde-labeled from the suprachiasmatic nuclei were no longer intrinsically photosensitive, although their number, morphology, and projections… 
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