| Registro completo |
| Provedor de dados: |
Biol. Res.
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| País: |
Chile
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| Título: |
Effects of g-hexachlorocyclohexane and L-3,3',5- triiodothyronine on rat liver cytochrome P4502E1- dependent activity and content in relation to microsomal superoxide radical generation
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| Autores: |
FERNÁNDEZ,VIRGINIA
MASSA,LAURA
QUIÑONES,LUIS
SIMON-GIAVAROTTI,KARIN A
GIAVAROTTI,LEANDRO
D'ALMEIDA,VÂNIA
AZZALIS,LIGIA A
JUNQUEIRA,VIRGINIA BC
VIDELA,LUIS A
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| Data: |
2003-01-01
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| Ano: |
2003
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| Palavras-chave: |
G-Hexachlorocyclohexane L-3
3'
5-Triiodothyronine Superoxide radical Cytochrome P4502E1 Rat liver
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| Resumo: |
Liver microsomal cytochrome P4502E1-dependent p-nitrophenol (PNP) hydroxylation and expression of cytochrome P4502E1 were studied in rats subjected to g-hexachlorocyclohexane (HCCH) or L-3,3,,5-triiodothyronine (T3) administration as a possible mechanism contributing to superoxide radical (O2.-) generation. HCCH treatment (a single dose of 40 mg/kg body wt) produced a 43% increase in the content of total cytochrome P450, whereas T3 (daily doses of 0.1 mg/kg body wt for two consecutive days) led to a 37% decrease. NADPH-dependent O2.- generation was elevated by HCCH and T3, expressed as either per mg of protein or per nmol of cytochrome P450, with a 135% enhancement in the O2.- production/superoxide dismutase (SOD) activity ratios being observed in both conditions. This was partly due to depression of SOD activity. Concomitantly, the molecular activity of NADPH-cytochrome p450 reductase was enhanced by 90 and 69% by HCCH and T3, respectively. In these conditions, microsomal PNP hydroxylation showed increases of 58 and 45% in HCCH- and T3-treated rats over control values, respectively, with a parallel 31% (HCCH) and 41% (T3) enhancement in the content of cytochrome P4502E1 assessed by western immunoblotting. We conclude that HCCH and T3 enhance the expression and activity of cytochrome P4502E1 and that of NADPH-cytochrome P450 reductase in rat liver, regardless of the changes in total cytochrome P450 content, representing major contributory mechanisms to microsomal NADPH-dependent O2.- generation
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| Tipo: |
Journal article
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| Idioma: |
Inglês
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| Identificador: |
http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602003000300007
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| Editor: |
Sociedad de Biología de Chile
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| Formato: |
text/html
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| Fonte: |
Biological Research v.36 n.3-4 2003
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