Related Experiment Video
Updated: Aug 10, 2026
Modeling Encephalopathy of Prematurity Using Prenatal Hypoxia-ischemia with Intra-amniotic Lipopolysaccharide in Rats
Published on: November 20, 2015
The effect of low level lead exposure on the postnatal structuring of the rat cerebellum
F Hasan1, G R Cookman, G J Keane
1Department of Pharmacology, University College, Belfield, Dublin, Ireland.
Insights
Chronic low-level lead exposure in rat pups did not affect cerebellar development or cell numbers. However, lead exposure did alter DNA biosynthesis rates, suggesting changes in the cell cycle during development.
Area of Science:
- Neuroscience
- Developmental Biology
- Toxicology
Background:
- Lead exposure is a significant public health concern, particularly for developing organisms.
- Understanding the neurodevelopmental effects of low-level lead exposure is crucial for setting safety guidelines.
Purpose of the Study:
- To investigate the impact of chronic low-level lead exposure on the early structural development of the rat cerebellum.
- To assess the effects of lead on cerebellar cell acquisition, migration, and DNA biosynthesis.
Main Methods:
- Exposure of rat pups to lead (less than 45 µg/dL blood).
- Monitoring cerebellar cell acquisition, migration, and final cell numbers.
- Assessing DNA biosynthesis rates and cell cycle parameters.
- Conducting morphometric studies on cerebellar cell layers.
Main Results:
- No significant alterations in cerebellar cell acquisition, migration, or final cell numbers were observed.
- Lead-exposed pups showed elevated DNA biosynthesis rates, suggesting a lengthened cell cycle.
- A delay in DNA biosynthetic rate increase was noted in neuron-enriched fractions from lead-exposed pups.
- Morphometric analyses confirmed no differences in cell viability or migration from the external granular layer.
Conclusions:
- Chronic low-level lead exposure does not significantly impact the early structural organization of the developing cerebellum in rats.
- Lead exposure may influence cell cycle dynamics, specifically DNA biosynthesis, without affecting overall cerebellar cell development.
Abstract:
Exposure of rat pups to lead (less than 45 micrograms/dl blood) caused no alterations in the rate of cerebellar cell acquisition, migration or final number when compared with age-matched controls. The rate of DNA biosynthesis was higher in the lead-exposed animals compared to controls and remained elevated until postnatal day 10. This observation suggests lengthening of the cell cycle. The expected increase in DNA biosynthetic rate was delayed in neuron-enriched fractions obtained from lead-exposed pups. This may have been due to the isolation procedure specifically selecting internal granular layer cells which migrated precociously during a protracted G1 phase in a lead-impaired cell cycle. Morphometric studies revealed no difference in the number, viability and migration of cells within and from the external granular layer of the cerebellum of lead-exposed animals. It is concluded that chronic low level lead exposure has no significant effect on the early structuring of the developing cerebellum.
