NMDAR-2A subunit protein expression is reduced in the hippocampus of rats exposed to Pb super(2+) during development

Chronic exposure to lead (Pb super(2+)) produces deficits of learning and memory in children and spatial learning deficits in developing rats. The N-methyl-d-aspartate receptor (NMDAR) has been identified as a principal target for Pb super(2+)-induced neurotoxicity. Age-dependent changes in NMDAR subunit gene expression were observed in hippocampi of rats chronically exposed to Pb super(2+) during development. These changes were present at blood Pb super(2+) levels ranging from 20-60 mu g/dl. Littermates were used in the present study to determine whether the changes in gene expression were reflected in protein levels. NR1, NR2A, and NR2B subunit protein levels were measured in rat hippocampus and cortex at post-natal days (PND) 7, 14, 21, and 28 by Western blot and densitometric analysis. A treatment effect was apparent for NR2A subunit protein expression in the hippocampus (F sub(1,28)=10.224, p