Developmental lead exposure causes spatial learning deficits in adult rats.
Groups of male rats exposed to lead (Pb) during different developmental periods were tested as adults in a water maze. A highly significant (P < 0.01) impairment in water maze performance was measured in rats exposed to Pb only during gestation and lactation (maternal exposure). At the time of testing (100-106 days old), blood and brain Pb concentrations were at control levels. Significant impairments (P < 0.05) were also present in rats continuously exposed to Pb from conception through adulthood. Post-weaning Pb exposure alone did not result in impaired performance despite significantly elevated blood and brain Pb levels at the time of testing. This study supports the hypothesis that a window of vulnerability to Pb neurotoxicity exists in the developing brain and that Pb exposure can result in long-term cognitive deficits.
Kuhlmann
A C
AC
The Johns Hopkins University, School of Hygiene and Public Health, Baltimore, MD 21205, USA.
McGlothan
J L
JL
Guilarte
T R
TR
D000704:Analysis of Variance; D000818:Animals; D001921:Brain / Q000187:drug effects* / Q000196:embryology; D005314:Embryonic and Fetal Development / Q000187:drug effects; D007855:Lead Poisoning / Q000523:psychology*; D007859:Learning Disabilities / Q000139:chemically induced*; D008297:Male; D018782:Maze Learning / Q000187:drug effects*; D051381:Rats