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PubMed · 7782558

Decrease in hepatotoxicity by lead exposure is not explained by its mitogenic response.

E J Calabrese·L A Baldwin·D A Leonard·X Q Zhao
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Abstract

The present research was conducted to evaluate the effect of mitogen pre-exposure on CCl4-induced hepatotoxicity. Male Wistar rats were administered a single i.p. injection of CCl4 (0.3 ml kg-1 in corn oil) 48 h following either a single dose of lead nitrate (0.33 mg kg-1) or distilled water via i.v. injection. Hepatotoxicity, as measured by serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, was monitored 6, 24, 48, 72 and 120 h after CCl4 exposure. The lead nitrate-pretreated rats displayed markedly lower serum ALT and AST levels at 24, 48 and 72 h than rats pretreated with distilled water. However, treatment with the antimitotic agent colchicine did not alter the lead-induced protection. These findings suggest that the lead-induced protection is not associated with the major mitogenic response of lead, despite its strong temporal association. A critical review of the available toxicological data also argues against the lead protection being a function of its capacity to inhibit cytochrome P-450.

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Alanine TransaminaseAnimalsAspartate AminotransferasesBody WeightCarbon TetrachlorideChemical and Drug Induced Liver InjuryColchicineCytochrome P-450 Enzyme SystemInjections, IntravenousLeadLiver DiseasesMaleMitogensNitratesRatsRats, WistarJournal Article

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E J Calabrese, L A Baldwin, D A Leonard, X Q Zhao. Decrease in hepatotoxicity by lead exposure is not explained by its mitogenic response.. https://doi.org/10.1002/jat.2550150212

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