Linked Life Data

2568902

Source:http://linkedlifedata.com/resource/pubmed/id/2568902

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1989-9-1
pubmed:abstractText
Recent studies from our laboratory have shown relatively high levels of polymorphic N-acetyltransferase (NAT)(EC 2.3.1.5) activity toward carcinogenic arylamines in urinary bladder cytosol of humans and in the inbred hamster model of the N-acetylation polymorphism. The expression of this polymorphism is of interest because of the higher incidence of bladder cancer among human slow acetylators with documented exposures to arylamine bladder carcinogens. In this study, arylamine NAT activity was partially purified and characterized in inbred hamster urinary bladder cytosols of defined acetylator genotype. Acetylator gene-dose response relationships were observed for the N-acetylation of p-aminobenzoic acid, p-aminosalicyclic acid, and the arylamine carcinogens 2-aminofluorene, 4-aminobiphenyl, and beta-naphthylamine in hamster bladder cytosol. Partial purification of hamster bladder cytosol by anion-exchange fast protein liquid chromatography yielded two NAT isozymes that catalyzed the N-acetylation of each of the arylamine substrates. The catalytic activity of the first isozyme was acetylator genotype-dependent (polymorphic), whereas the second isozyme appeared to be acetylator genotype-independent (monomorphic). Catalytic activities between homozygous rapid, heterozygous, and homozygous slow acetylator genotypes were compared with respect to both initial rates and apparent maximum velocities. Comparison of homozygous rapid and slow acetylator bladder cytosol showed that the apparent Vmax for 2-aminofluorene NAT activity was significantly higher in rapid than slow acetylators (6-fold in cytosol, 50-fold in the polymorphic NAT isozyme). These results suggest a key role for a polymorphic NAT isozyme, regulated by the acetylator genotype and expressed in urinary bladder cytosol, in the initiation of bladder cancer via arylamine carcinogens.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0090-9556
pubmed:author
pubmed:issnType
Print
pubmed:volume
17
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
231-7
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:articleTitle
Identification and kinetic characterization of acetylator genotype-dependent and -independent arylamine carcinogen N-acetyltransferases in hamster bladder cytosol.
pubmed:affiliation
Department of Pharmacology, Morehouse School of Medicine, Atlanta, GA 30310-1495.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S.