Abstract
Purpose: :
GNAT2-DTA mouse expresses diphtheria toxin under a cone-specific human cone transducin alpha-subunit (GNAT2) promoter (Fong et al., 2005). In this mouse line, both cone and rod photoreceptors fail to ever develop at all in the ventral retina. In this study, we try to understand whether loss of photoreceptors may have effects on retinal ganglion cell (RGC) function during early development.
Methods: :
We used 60-channel multi-electrode array (MEA) recordings to quantify patterns of spontaneous and light evoked retinal ganglion cell activity in GNAT2-DTA mice and wild type mice at different postnatal ages
Results: :
1. At postnatal day 6, the spontaneous waves of correlated RGC activity in GNAT-DTA mice were similar to those in wild-type mice. 2. In GNAT-DTA strain, spontaneous firing rates increased by P12. 3. At P12, full-field light flashes evoked reliable responses in many RGCs in GNAT-DTA mice strains, with equal preservation of on and off responses.
Conclusions: :
Although cone and rod photoreceptors in the ventral retina of GNAT-DTA mice were never develop, the activity of many RGCs of GNAT-DTA mice remained normal.
Keywords: retinal degenerations: cell biology • retinal development • electrophysiology: non-clinical