LOCALIZATION OF THE GLUTAMATE TRANSPORTER GLT-1 IN RAT AND MACAQUE MONKEY RETINAE

Antibodies directed against a glutamate transporter (GLT-1) purified f rom rat brain were applied to cryostat sections of rat and macaque mon key retinae. In the brain, GLT-1 expression is found mainly in astrocy tes, and therefore it has been suggested that GLT-1 may be a glutamate transporter specific to glial cells. However, in the rat retina, cone s and two distinct cone bipolar cell types were strongly immunoreactiv e. In the monkey retina, flat midget bipolars and one diffuse bipolar cell type (DB2)), were found to be labelled. Muller cells or astrocyte s, the neuroglial cells of rat and monkey retinae, were not GLT-1-immu noreactive.