Journal
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
Volume 105, Issue 37, Pages 14181-14186Publisher
NATL ACAD SCIENCES
DOI: 10.1073/pnas.0803893105
Keywords
adaptation; dopamine; melanopsin; photoreception; vision
Categories
Funding
- National Institutes of Health [R03 EY0107032, F32 EY16678, K99 EY18863, R01 EY12793, R01 EY17137, NS 035615, EY 17809, R01 EY15815, EY9256]
- Vanderbilt Vision Core [P30-EY008126]
Ask authors/readers for more resources
Retinal dopaminergic amacrine neurons (DA neurons) play a central role in reconfiguring retinal function according to prevailing illumination conditions, yet the mechanisms by which light regulates their activity are poorly understood. We investigated the means by which sustained light responses are evoked in DA neurons. Sustained light responses were driven by cationic currents and persisted in vitro and in vivo in the presence of: L-AP4, a blocker of retinal ON-bipolar cells. Several characteristics of these. L-AP4-resistant light responses suggested that they were driven by melanopsin-expressing intrinsically photosensitive retinal ganglion cells (ipRGCs), including long latencies, marked poststimulus persistence, and a peak spectral sensitivity of 478 nm. Furthermore, sustained DA neuron light responses, but not transient DA neuron responses, persisted in rod/cone degenerate retinas, in which ipRGCs account for virtually all remaining retinal phototransduction. Thus, ganglion-cell photoreceptors provide excitatory drive to DA neurons, most likely by way of the coramification of their dendrites and the processes of DA neurons in the inner plexiform layer. This unprecedented centrifugal outflow of ganglion-cell signals within the retina provides a novel basis for the restructuring of retinal circuits by light.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available