Summary
This study characterizes a double-mutant mouse model (Opn4⁻/⁻ × Pde6b^rd10/rd10) that eliminates all retinal photosensitivity by combining rod/cone degeneration with melanopsin knockout, creating a model of absolute blindness. For lighting researchers, this model provides a tool to isolate the contributions of ipRGCs and classical photoreceptors to non-visual light responses such as circadian entrainment and the pupillary light reflex.
Key Findings
- Complete abolition of the pupillary light reflex in double-mutant mice (Opn4⁻/⁻ × Pde6b^rd10/rd10), confirmed by behavioral and electrophysiological testing.
- Full-field ERG (fERG), pattern ERG (pERG), and visual evoked potentials (VEP) were entirely absent in the double-mutant model.
- Behavioral tests showed complete loss of light aversion (no rejection of illuminated spaces) and zero measurable visual acuity via optomotor test.
- Immunohistochemistry confirmed marked degeneration of outer retinal layers and complete absence of melanopsin staining, validating total elimination of all photosensitive retinal elements.
Categories
The Science of Light: Characterizes a double-mutant mouse model lacking both rod/cone photoreceptors and melanopsin-expressing ipRGCs, enabling study of the full scope of retinal photosensitivity including non-visual light responses.
Eye Health & Vision: Demonstrates complete loss of visual function and pupillary light reflex through ERG, VEP, and behavioral testing, relevant to understanding retinal degeneration and blindness models.
Author(s)
S Milla-Navarro, M Pazo-González, F Germain
Publication Year
2022
Number of Citations
2
Related Publications
The Science of Light
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- Diminished pupillary light reflex at high irradiances in melanopsin-knockout mice
- Melanopsin is required for non-image-forming photic responses in blind mice
Eye Health & Vision
- Diminished pupillary light reflex at high irradiances in melanopsin-knockout mice
- Genetic reactivation of cone photoreceptors restores visual responses in retinitis pigmentosa
- Melanopsin and rod–cone photoreceptors play different roles in mediating pupillary light responses during exposure to continuous light in humans
- Characteristic patterns of dendritic remodeling in early-stage glaucoma: evidence from genetically identified retinal ganglion cell types
- Intrinsically photosensitive melanopsin retinal ganglion cell contributions to the pupillary light reflex and circadian rhythm