The BN rat strain carries dominant hepatocarcinogen resistance loci.
The phylogenetically distant F344 and BN rat strains and their (BN x F344) F1 hybrids were compared for susceptibility to hepatocarcinogenesis using the 'resistant hepatocyte' model. Quantitative stereological analysis of frequency (number/liver) and size (mean volume and volume fraction) of placental form glutathione S-transferase (GST-P)-positive lesions was carried out at 8, 15 and 32 weeks after diethylnitrosamine initiation. The number/liver of GST-P-positive lesions at any time point was slightly higher in BN and (BN x F344) F1 rats than in F344 rats, but not statistically different. However, mean volume and volume fraction of GST-P positive lesions were much higher in F344 than in both BN and (BN x F344) F1 rats at any time point, with a difference of up to > 10-fold. GST-P-positive lesions exhibited a significantly higher labeling index and much lower remodeling in male F344 than in BN and (BN x F344) F1 rats. HCCs were present at 54-57 weeks after initiation in 77% of male F344 and in no (BN x F344) F1 rats and at 70 weeks HCCs were observed in 100% of male F344 and in 23% of (BN x F344) F1 rats. These results suggest that the BN rat strain is resistant to hepatocarcinogenesis and that its resistance is genetically transmitted as a dominant character to F1 hybrids of the BN strain with the F344 susceptible strain.
Pascale
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RM
Istituto di Patologia Generale e Centro di Ricerche Oncologiche, Università di Sassari, Italy.
Simile
M M
MM
DeMiglio
M R
MR
Muroni
M R
MR
Gaspa
L
L
Dragani
T A
TA
Feo
F
F
D015073:2-Acetylaminofluorene / Q000633:toxicity*; D000818:Animals; D001835:Body Weight; D002273:Carcinogens / Q000633:toxicity*; D005799:Genes, Dominant; D020022:Genetic Predisposition to Disease; D005982:Glutathione Transferase / Q000378:metabolism; D007527:Isoenzymes / Q000378:metabolism; D008099:Liver / Q000201:enzymology; D008114:Liver Neoplasms, Experimental / Q000139:chemically induced* / Q000235:genetics; D008297:Male; D009929:Organ Size; D010802:Phylogeny; D051381:Rats; D011914:Rats, Inbred BN; D011916:Rats, Inbred F344; D013045:Species Specificity
D002273:Carcinogens; D007527:Isoenzymes; D015073:2-Acetylaminofluorene; D005982:Glutathione Transferase