Ontogenetic changes in the projections of neocortical neurons

摘要: Development changes in the origins of contra- and ipsilateral projections from rat parietal cortex were examined using retrograde transport horseradish peroxidase fluorescent dyes fast blue nuclear yellow. The aim study was to determine fate neurons which send axons through corpus callosum neonatal, but not young adult, rat. 1. Neurons project across at postnatal day 8 (PND 8), PND 20 or later, do die; they merely lose their contralateral processes. 2. At 8, many these neurons--in particular, those lamina Va barrel field area--project simultaneously motor cortex. 3. By area still callosum. We conclude that least some neocortical initially elaborate more axonal processes than will maintain selectively eliminate major during development.