Long-term evolution of excitotoxic cortical dysgenesis induced in the developing rat brain.

Cortical dysplasias are frequently caused by excitotoxic brain damage due to hypoxia or ischemia during development. Ibotenate, a glutamatergic agonist, was injected in the neopallium of rat pups at day of birth. The resulting cytoarchitectonic pattern includes neuronal depopulation in deep cortical layers, sulcus formation, and molecular ectopias, mimicking human polymicrogyria and disorders of neuronal migration. These cortical dysplasias persist until adulthood, providing a rat model to investigate the long-term functional consequences of cortical malformations.