Linked Life Data

10036221

Source:http://linkedlifedata.com/resource/pubmed/id/10036221

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1999-3-16
pubmed:abstractText
Long-Evans rats (strain Turku AB; L-E) are at least 1000-fold more sensitive (LD50 about 10 microg/kg) to the acute lethal effects of 2, 3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) than are Han/Wistar (Kuopio; H/W) rats (LD50 > 9600 microg/kg). The AH receptor (AHR) is believed to mediate the toxic effects of TCDD and related halogenated aromatic hydrocarbons. We compared the AHRs of L-E and H/W rats to determine if there were any structural or functional receptor differences that might be related to the dramatic difference in the sensitivity of these two strains to the lethal effects of TCDD. Cytosols from liver and lung of the sensitive L-E rats contained about twofold higher levels of specific binding sites for [3H]TCDD than occurred in H/W rats; the Kd for binding of [3H]TCDD to AHR in hepatic cytosols was similar between the two strains. Addition of the oxyanions, molybdate or tungstate (20 mM), had little effect upon ligand binding to AHR in hepatic cytosols from L-E rats whereas in cytosols from H/W rats these agents substantially diminished or totally abolished TCDD binding. The AHR in H/W cytosols also lost ligand-binding function when NaCl (20 to 400 mM) was added to the buffer whereas, in cytosols from L-E rats, the addition of 400 mM NaCl caused the receptor complex to shift from 9S to 6S during velocity sedimentation but did not destroy ligand binding function. AHR from hepatic cytosol of both the L-E and H/W rats could be transformed to the DNA-binding state in the presence of TCDD or other dioxin congeners as assessed by gel mobility shift assays. The most dramatic difference in AHR properties between L-E and H/W rats is molecular mass. Immunoblotting of cytosolic proteins revealed that the AHR in L-E rats has an apparent mass of approximately 106 kDa, similar to the mass of the receptor previously reported in several other common laboratory rat strains. In contrast, the mass of the AHR in H/W rats is approximately 98 kDa, significantly smaller than the mass of receptor reported in any other rat strains. F1 offspring of a cross between L-E and H/W rats expressed both the 106- and the 98-kDa protein. There was no apparent difference in the mass of the AHR nuclear translocator protein (ARNT) between the two strains, but the hepatic concentration of ARNT was about three times as high in L-E as in H/W rats. It will be interesting to find out how the altered structure of the AHR in H/W rats is related to their remarkable resistance to the lethal effects of TCDD.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0041-008X
pubmed:author
pubmed:copyrightInfo
Copyright 1999 Academic Press.
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
155
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
82-95
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:10036221-Animals, pubmed-meshheading:10036221-Aryl Hydrocarbon Receptor Nuclear Translocator, pubmed-meshheading:10036221-Cytochrome P-450 CYP1A1, pubmed-meshheading:10036221-DNA, pubmed-meshheading:10036221-DNA-Binding Proteins, pubmed-meshheading:10036221-Drug Resistance, pubmed-meshheading:10036221-Female, pubmed-meshheading:10036221-Male, pubmed-meshheading:10036221-Mice, pubmed-meshheading:10036221-Mice, Inbred C57BL, pubmed-meshheading:10036221-Molecular Weight, pubmed-meshheading:10036221-Rats, pubmed-meshheading:10036221-Rats, Long-Evans, pubmed-meshheading:10036221-Rats, Sprague-Dawley, pubmed-meshheading:10036221-Rats, Wistar, pubmed-meshheading:10036221-Receptors, Aryl Hydrocarbon, pubmed-meshheading:10036221-Sodium Chloride, pubmed-meshheading:10036221-Species Specificity, pubmed-meshheading:10036221-Tetrachlorodibenzodioxin, pubmed-meshheading:10036221-Transcription Factors
pubmed:year
1999
pubmed:articleTitle
Physicochemical differences in the AH receptors of the most TCDD-susceptible and the most TCDD-resistant rat strains.
pubmed:affiliation
Department of Environmental Medicine, National Public Health Institute, Kuopio, FIN-70701, Finland.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't