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Updated: Aug 19, 2026

The Dimethylnitrosamine Induced Liver Fibrosis Model in the Rat
Published on: June 17, 2016
Erythrocyte uroporphyrinogen I synthase in rats treated with the hepatic carcinogen diethylnitrosamine
R W de Calmanovici1, A C Cochón, C A Aldonatti
1Laboratorio de Porfirias Experimentales y Metabolismo del Hemo, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Argentina.
Abstract:
Uroporphyrinogen I Synthase (URO-S) activity was measured in erythrocytes of female and male rats which had received diethylnitrosamine (DENA) as an inducer of hepatic tumors. Twenty-two weeks after the last dose of the carcinogen, the rats showed statistically significant increases in the URO-S activity. Differences in the body weight, erythrocyte porphyrin content or the hematocrit between treated and control rats were not found. Fifty percent of female rats and thirty percent of male rats treated with DENA were found to have hepatic tumors but there was no correlation between blood URO-S activity and tumoral development in spite of the increase in URO-S activity observed in DENA treated rats. This was observed both in male and female rats.
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