Linked Life Data

3099426

Source:http://linkedlifedata.com/resource/pubmed/id/3099426

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1987-2-10
pubmed:abstractText
Polycyclic aromatic hydrocarbons, e.g., 7,12-dimethylbenz(a)anthracene (DMBA), cause various toxic effects in rat testis. To clarify the mechanism of action of DMBA in adult rat testis microsomes and mitochondria from this organ were investigated in vitro with respect to their capacity to metabolize DMBA. Qualitatively, both preparations showed DMBA-hydroxylase activities which were influenced by cytochrome P-450 inhibitors, chelators, and free-radical scavengers, suggesting that the DMBA metabolism was accounted for by different metabolic pathways in these organelles. Metabolism of DMBA was also accompanied by a pronounced covalent binding to both microsomal and mitochondrial protein, catalyzed primarily by a free-radical mechanism involving free or loosely bound iron which may involve superoxide anion shown to be generated by testis mitochondria. With microsomes covalent binding was markedly enhanced by added horseradish peroxidase but not by hydrogen peroxide whereas the mitochondrial binding was affected neither by added horseradish peroxidase nor by hydrogen peroxide. Antibodies raised against cytochrome P-450 c from rat liver inhibited the microsomal DMBA-hydroxylase but not the mitochondrial DMBA metabolism. It is concluded that the microsomal DMBA conversion and covalent binding are due to a mixture of cytochrome P-450 and free-radical-dependent metabolic pathways whereas the corresponding mitochondrial reaction is due mainly to a free-radical-dependent pathway. However, the data do not allow for a conclusion as to the quantitative importance of these pathways. It is proposed that both pathways may be important in DMBA-dependent testis toxicity but also in polycyclic aromatic hydrocarbon-dependent testis toxicity in general.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0041-008X
pubmed:author
pubmed:issnType
Print
pubmed:volume
87
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
141-54
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
Evidence for a free-radical-dependent metabolism of 7,12-dimethylbenz(a)anthracene in rat testis.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't