F344/Shi rats bearing type b catalase-1 locus are sensitive to sodium L-ascorbate promotion of two-stage urinary bladder carcinogenesis.
Our previous data showed that F344/DuCrj and LEW/Crj rat strains bearing the type a catalase-1 locus (CS1a) are sensitive to the promoting activity of sodium L-ascorbate (Na-AsA) in 2-stage urinary bladder carcinogenesis, whereas ODS/Shi and WS/ Shi rat strains bearing the type b catalase-1 locus (CS1b) are resistant. In present study, we investigated the susceptibility of F344/Shi rats also bearing the CS1 to the Na-AsA-promoting effects on bladder tumor development. Male rats, 6 weeks old, were given 0.05% N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) in their drinking water for 4 weeks, then fed either basal diet supplemented with 5% Na-AsA or no chemicals for 32 weeks. The rats given BBN alone had a few small carcinomas in the urinary bladder. In contrast, animals administered BBN-Na-AsA had many large carcinomas. Administration of Na-AsA was associated with significant elevation of urinary pH and L-ascorbic acid. The results indicate that F344/Shi rats are sensitive to the promoting effects of Na-AsA on 2-stage urinary bladder carcinogenesis, and thus that the CS1 locus may not influence susceptibility to promotion.
Mori
S
S
First Department of Pathology, Osaka City University Medical School, Osaka, Japan.
Murai
T
T
Hosono
M
M
Yamashita
H
H
Oohara
T
T
Makino
S
S
Doteuchi
M
M
Fukushima
S
S
D000483:Alleles; D000818:Animals; D001205:Ascorbic Acid / Q000633:toxicity*; D002085:Butylhydroxybutylnitrosamine / Q000633:toxicity; D002273:Carcinogens / Q000633:toxicity*; D002295:Carcinoma, Transitional Cell / Q000139:chemically induced / Q000235:genetics / Q000473:pathology; D002374:Catalase / Q000235:genetics*; D004198:Disease Susceptibility; D006965:Hyperplasia; D008297:Male; D018307:Neoplasms, Squamous Cell / Q000139:chemically induced / Q000235:genetics / Q000473:pathology; D010212:Papilloma / Q000139:chemically induced / Q000235:genetics / Q000473:pathology; D051381:Rats; D011916:Rats, Inbred F344 / Q000235:genetics*; D001749:Urinary Bladder Neoplasms / Q000139:chemically induced / Q000235:genetics* / Q000473:pathology
D002273:Carcinogens; D002085:Butylhydroxybutylnitrosamine; C108078:catalase I; D002374:Catalase; D001205:Ascorbic Acid