Characterization of Gabaergic Horizontal Cells in the Mouse Retina
The inner nuclear layer of the mammalian retina contains the cell bodies of the amacrine, bipolar and horizontal neurons. About 90% of the amacrine neurons are glycinergic and GABAergic and marked by the expression of the vesicular inhibitory amino acid transporter, VIAAT. By contrast, the phenotype in horizontal inhibitory neurons vary among different mammals. In the primate retina, experimental evidence suggests the absence of VIAAT and hypothesizing that GABA could be released by efflux through the GABA transporters. On the other hand, in rodents, the horizontal cells express the VIAAT and carry out vesicle-dependent GABA release. Although the retina cells have been extensively studied, the precise inhibitory repertoire of horizontal cells is not yet fully elucidated. In this study, we provide additional evidence of the GABAergic phenotype of horizontal cells in the mouse retina by using transgenic technology. Immunostaining of retinal sections from a transgenic line that expresses EGFP under the GAD67 promoter suggest that adult horizontal cells are devoid of GAD67 but contain GAD65. In addition, analysis of sections from a mouse expressing ChR2-EYFP under the VIAAT promoter clearly label horizontal and amacrine cells. Undergoing work will better define a GABAergic character of mouse horizontal cells and contribute to the understanding the basic chemo- architecture of the rodent retina.
Uresti, Zulema, "Characterization of Gabaergic Horizontal Cells in the Mouse Retina" (2021). ETD Collection for University of Texas, El Paso. AAI28541070.