GLUT2 expression in the rat retina: localization at the apical ends of Müller cells.

In order to understand the molecular basis of glucose regulation supporting visual function, this study examined the presence of GLUT2, a facilitated-diffusion glucose transporter isoform, and delineated its localization in the rat retina. Reverse transcriptase-polymerase chain reaction (RT-PCR) demonstrated the presence of GLUT2 mRNA, and immunoblot analysis using polyclonal antibody specific to rat GLUT2 revealed a band at a molecular weight of approximately 60 kDa, indicating the presence of GLUT2 protein in the rat retina. Fluorescence and electron microscopy localized GLUT2 expression to the apical ends of Müller cells that face the inter-photoreceptor space.