Changes in liver fatty acid-binding protein in rat enzyme-altered foci.
The level of liver fatty acid-binding protein (L-FABP) was analyzed in enzyme-altered foci (EAF) positive for GST-P, or after classification of foci into different subclasses by haematoxylin and eosin staining. Rats were treated with either an initiating single dose of diethylnitrosamine (DEN) followed by no treatment, treatment with phenobarbital, PCB, nafenopin or repeated injections of DEN, or alternatively non-treated or treated with nafenopin alone. Changes in the level of L-FABP were detected in the majority of EAF and both L-FABP-positive and -negative foci were seen. However, in rats initiated with DEN, EAF were almost exclusively L-FABP-negative. The fraction of L-FABP-negative foci increased with increasing foci size, while the time of treatment or the dose of the promoter did not seem to have any effect. It was also found that treatment with DEN gave a higher fraction of L-FABP-negative foci as compared to treatment with phenobarbital or PCB, indicating a specific effect of DEN. These data together with previously published findings suggest that L-FABP expression in EAF is determined by the initiating carcinogenic regimen and that it might be possible to use the expression of L-FABP in tumours to differentiate initiating chemicals.
Thullberg
M
M
Department of Toxicology and Chemistry, National Institute for Working Life, Solna, Sweden.
Grasl-Kraupp
B
B
Högberg
J
J
Garberg
P
P
D000818:Animals; D000918:Antibody Specificity; D002273:Carcinogens / Q000008:administration & dosage / Q000494:pharmacology*; D002352:Carrier Proteins / Q000032:analysis* / Q000276:immunology; D004052:Diethylnitrosamine / Q000494:pharmacology*; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D005260:Female; D006498:Hepatectomy; D007106:Immune Sera; D008099:Liver / Q000737:chemistry* / Q000201:enzymology; D018996:Myelin P2 Protein / Q000032:analysis* / Q000276:immunology; D009255:Nafenopin / Q000494:pharmacology; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D010634:Phenobarbital / Q000494:pharmacology; D011078:Polychlorinated Biphenyls / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley
D002273:Carcinogens; D002352:Carrier Proteins; C493320:Fabp1 protein, mouse; C493321:Fabp1 protein, rat; C490174:Fabp7 protein, rat; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D007106:Immune Sera; D018996:Myelin P2 Protein; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D009255:Nafenopin; D004052:Diethylnitrosamine; D011078:Polychlorinated Biphenyls; D010634:Phenobarbital