EXPRESSION OF DMAP-45R IN THE RAT VISUAL-CORTEX IS MODULATED BY VISUAL EXPERIENCE

Effects of visual experience upon expression of a developmentally regu lated microtubule-associated protein (MAP) were studied in the visual cortex of monocularly deprived rats. The antibody Drosophila MAP-45 (D MAP-45) recognizes proteins in the developing ventral nerve cord of Dr osophila and in rat brain. Monocular deprivation from day 12, before e ye opening, to day 80 reduced the number of DMAP-45 immunoreactive lay er V pyramidal cell apical dendrites in the monocular segment (Oc1M) o f the visual cortex contralateral to the deprived eye. No significant visual deprivation effects were seen in the binocular segment (Oc1B). Immunoreactivity was restored to control levels in Oc1M of rats in whi ch the monocular sutures were removed at day 75, subsequently allowing 5 days of exposure to light. These results indicate potential involve ment of this MAP in experience-dependent structural plasticity.