Development of pyramidal cells in medial frontal cortex following neonatal lesions of anterior midline cortex

The anterior midline cortex of rats was removed on postnatal day 10. The development of layer II, III and V pyramidal cells in the tissue that subsequently formed the presumptive medial frontal cortex in these animals was studied in Golgi-Cox stained material on postnatal days 15, 25, 35, and 120. The results showed that the number of branch segments of both basilar and apical dendrites were significantly reduced relative to controls at the early developmental stages but by adulthood all regions analyzed were similar in operates and controls. Thus, the cells migrating into the lesion area were delayed in development but did eventually grow to resemble cells that were in the same region in normal controls. This anatomical development correlates with the functional recovery of animals with day 10 frontal lesions in other studies, and suggests that the growth of this tissue may play a role in functional recovery.