First Author | Bush RA | Year | 2019 |
Journal | Invest Ophthalmol Vis Sci | Volume | 60 |
Issue | 10 | Pages | 3680-3688 |
PubMed ID | 31469895 | Mgi Jnum | J:279115 |
Mgi Id | MGI:6359929 | Doi | 10.1167/iovs.19-27242 |
Citation | Bush RA, et al. (2019) Cone ERG Changes During Light Adaptation in Two All-Cone Mutant Mice: Implications for Rod-Cone Pathway Interactions. Invest Ophthalmol Vis Sci 60(10):3680-3688 |
abstractText | Purpose: The b-wave of the cone ERG increases in amplitude and speed during the first few minutes of adaptation to a rod-suppressing background light. Earlier studies implicate rod pathway input to the cone pathway in these changes. Methods: The timing and amplitude of the cone b-wave and isolated oscillatory potentials (OP) during the first 10 minutes of light adaptation in wild-type (WT) mice and two mutant lines without functional rods was examined: rhodopsin knockout (Rho-/-), lacking rod outer segments, and NRL knockout (Nrl-/-), in which rods are replaced by S-cones. Expression of the immediate-early gene c-fos, which is increased in the inner retina by light-induced activity, was evaluated by immunohistochemistry in dark- and light-adapted retinas. Results: WT b-wave and OP amplitudes increased, and implicit times decreased during light adaptation. Subtracting OP did not alter b-wave changes. Rho-/- b-wave and OP amplitudes did not increase during adaptation. B-wave timing and amplitude and the timing of the major OP at 1 minute of adaptation were equivalent to WT at 10 minutes. The light-adapted ERG b-wave in Nrl-/- mice, which originates in both the rod and cone pathways, changed in absolute amplitude and timing similar to WT. C-fos expression was present in the inner retinas of dark-adapted Rho-/- but not WT or Nrl-/- mice. Conclusions: Activity in the distal rod pathway produces changes in the cone ERG during light adaptation. Rods in Rho-/- mice constitutively activate this rod-cone pathway interaction. The rod pathway S-cones in Nrl-/- mice may maintain the WT interaction. |