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lead acetate toxicity in vitro: dependence on the cell composition of the cultures.
zurich m.g., monnet-tschudi f., bérode m., honegger p.
it is well known that exposure to low doses of lead causes long-lasting neurobehavioural deficits, but the cellular changes underlying these behavioural changes remain to be elucidated. a protective role of glial cells on neurons through lead sequestration by astrocytes has been proposed. the possible modulation of lead neurotoxicity by neuron-glia interactions was examined in three-dimensional cultures of foetal rat telencephalon. mixed-brain cell cultures or cultures enriched in either neurons or glial cells were treated for 10 days with lead acetate (10(-6) m), a concentration below the limit of cytotoxicity. intracellular lead content and cell type-specific enzyme activities were determined. it was found that in enriched cultures neurons stored more lead than glial cells, and each cell type alone stored more lead than in co-culture. moreover, glial cells but not neurons were more affected by lead in enriched culture than in co-culture. these results show that neuron-glia interactions attenuate the cellular lead uptake and the glial susceptibility to lead, but they do not support the idea of a protective role of astrocytes.

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The text includes 74 "a"s in total.
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