Behavioral effects of neonatal and adult excitotoxic lesions of the mediodorsal thalamus in the adult rat.

We examined in the rat, the effects of neonatal (postnatal Day 7) and adult excitotoxic lesions of the mediodorsal thalamus (MDT), a brain area innervating the prefrontal cortex and implicated as a site of neuropathology in schizophrenia. Previous studies showed that rats with neonatal excitotoxic damage of the ventral hippocampus (VH), used as an animal model of this disorder, display in young adulthood a variety of abnormalities reminiscent of schizophrenia, including hyperactivity to stressful stimuli and amphetamine. It has been speculated that behavioral abnormalities of the neonatally VH lesioned animals are mediated through MDT projections to the prefrontal cortex.