US EPA

1005052 

Journal Article 

Toxic effects of lead and nickel nitrate on rat liver chromatin components 

Rabbani-Chadegani Iii, A; Fani, N; Abdossamadi, S; Shahmir, N 

2011 

No 

Journal of Biochemical and Molecular Toxicology
ISSN: 1095-6670
EISSN: 1099-0461 

25 

3 

127-134 

English 

21080481 

10.1002/jbt.20368 

The biological activity of heavy metals is related to their physicochemical interaction with biological receptors. In the present study, the effect of low concentrations of nickel nitrate and lead nitrate (<0.3 mM) on rat liver soluble chromatin and histone proteins was examined. The results showed that addition of various concentrations of metals to chromatin solution preceded the chromatin into aggregation and precipitation in a dose-dependant manner; however, the extent of absorbance changes at 260 and 400 nm was different between two metals. Gel electrophoresis of histone proteins and DNA of the supernatants obtained from the metal-treated chromatin and the controls revealed higher affinity of lead nitrate to chromatin compared to nickel nitrate. Also, the binding affinity of lead nitrate to histone proteins free in solution was higher than nickel. On the basis of the results, it is concluded that lead reacts with chromatin components even at very low concentrations and induce chromatin aggregation through histone-DNA cross-links. Whereas, nickel nitrate is less effective on chromatin at low concentrations, suggesting higher toxicity of lead nitrate on chromatin compared to nickel. © 2010 Wiley Periodicals, Inc. J Biochem Mol Toxicol 00:1-8, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/jbt.20368.