Pii: S0304-3940(01)02045-6

Rats prenatally exposed to the neurotoxins methylazoxymethanol (MAM) or 5-Bromo-2 0-deoxyuridine (BrdU) are used as animal models of brain maldevelopment. We administered in rats MAM (20 mg/kg), or BrdU (100 mg/kg) or both at gestational day 11. Locomotion was not affected by any prenatal treatment whereas learning was delayed in the Morris maze in MAM animals. BrdU induced decreased NGF and BDNF levels in the hippocampus. In the parietal cortex prenatal BrdU administration induced NGF potentation associated with decreased BDNF. Animals treated with both MAM and BrdU showed also an increased immunopositivity for choline acetyltransferase (ChAT) and low af®nity neurotrophins' receptor (p75) in the septum and Meynert's nuclei. These ®ndings suggest that embryonic exposure to MAM and/or BrdU may be useful for studying mechanisms associated with neurodegenerative diseases affecting brain morphology and behavior. q 2001 Elsevier Science Ireland Ltd. All rights reserved.