Behavioral effects of asymptomatic lead exposure during neonatal development in rats
Overmann, S.R.
Toxicology and Applied Pharmacology 41(3): 459-471
1977
ISSN/ISBN: 0041-008X PMID: 918981 Document Number: 115128
Long-Evans rats intubated daily from 3-21 days old with 0, 10, 30 or 90 mg/kg of lead acetate in aqueous solution were tested postweaning on 8 behavioral measures. The 3 levels of Pb exposure had no effect on growth, and all animals were overtly free of signs of poisoning. Neonatal Pb exposure produced subtle behavioral effects including increased motor activity (jiggle cages) and impairment of motor coordination (rotarod test), response inhibition ability (operant delayed response) and reversal learning of a tactually cued conditional discrimination. The Pb treatment had no effect on simple learning (turning response in E-maze), complex visually cued learning (conditional discrimination in E-maze) and visual acuity (optokinetic test). Acquisition and extinction of passive shock avoidance were not affected by Pb exposure, but acquisition and extinction of active avoidance were affected. Pb treatment also decreased hematocrit, increased blood Pb concentration, and increased adrenal and kidney wet weights.