FIG. 14.

Potential clinical relevance of ipRGCs. A: conventional RGCs in rod/cone-degenerated mice, driven to express melanopsin by viral transduction. Whole cell current-clamp recording in flat-mount retina to study their physiology (at 32–35°C) and Lucifer Yellow injection to study their morphology. Light responses from two cells consisting of a long-lasting depolarization and action-potential firing are shown (stimulus timing and duration indicated by a short black bar beneath the recorded trace). Conventional RGCs expressing melanopsin responded to light even in rod/cone-degenerate retina and under pharmacological block of synaptic transmission. Scale bars are 50 μm. B: visual discrimination task. Mice swam down a water-filled alley toward an illuminated or dark compartment, with the rewarded stimulus being paired with the location of a submerged platform. C: melanopsin-transduced (open circles) mice outperforming control-transduced (triangles) rod/cone-degenerated mice in the visual detection task over an 8-day trial. [A–C modified from Lin et al. (111).]