Linked Life Data

8389254

Source:http://linkedlifedata.com/resource/pubmed/id/8389254

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1993-7-6
pubmed:abstractText
Dog is an animal model for assessing aromatic amine-induced bladder cancer, and hepatic N-glucuronidation is proposed as an important pathway leading to initiation of carcinogenesis. Therefore, benzidine N-glucuronidation was evaluated with dog liver microsomes and slices. Microsomal benzidine UDP-glucuronosyltransferase activity was increased with a variety of detergents. For kinetic analysis, native microsomal preparations were separated into treated (detergent treated, not centrifuged) or soluble (detergent treated, centrifuged) fractions. The detergents Triton X-100, Lubrol PX, Emulgen 911 and CHAPS increased the specific activity of treated fractions relative to the native microsomes 3- to 6-fold. The specific activities of the soluble fractions were highest with Emulgen 911 and CHAPS at a detergent-to-protein ratio of 1. Subsequent studies used Emulgen 911 or CHAPS. Similar results were observed with either preparation. For treated preparations, the Km and Vmax values were 0.142 +/- 0.006 mM and 0.65 +/- 0.1 nmol/mg protein/min respectively. A variety of chemicals were tested for their effect on benzidine N-glucuronide formation. At 0.1 mM, the only effective inhibitors (< 50% of control) were 2-aminofluorene, estriol, 17-epiestriol, 2-OH-estrone, and 4-OH-estrone. With Emulgen-treated microsomes, the Ki values for 2-aminofluorene, 4-aminobiphenyl and estriol were 0.114 +/- 0.014, 0.347 +/- 0.032 and 0.047 +/- 0.003 mM respectively. 2-Aminofluorene and estriol were non-competitive inhibitors, while 4-aminobiphenyl was a competitive inhibitor. Slices incubated with these chemicals exhibited an inhibition profile similar to that observed with microsomes. Thus, N-glucuronidation of benzidine may be an important metabolic pathway in dog. Inhibition of benzidine N-glucuronidation by estriol and catechol estrones may be important in vivo events in aromatic amine-induced carcinogenesis.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0143-3334
pubmed:author
pubmed:issnType
Print
pubmed:volume
14
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
893-7
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Benzidine glucuronidation in dog liver.
pubmed:affiliation
VA Medical Center, St. Louis, MO.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, Non-P.H.S.