Ethoxyquin alone induces preneoplastic changes in rat kidney whilst preventing induction of such lesions in liver by aflatoxin B1.

Pretreatment of Fischer 344 rats with the antioxidant ethoxyquin (EQ), followed by administration of aflatoxin B1 (AFB1) in the continuing presence of EQ was used to examine the effect of the antioxidant on liver and kidney. EQ (0.5% in diet) completely prevented the formation of AFB1-induced preneoplastic liver lesions as judged by morphological alteration, or by markers such as gamma glutamyl transpeptidase, glutathione S-transferase P or J1, an unknown membrane-bound antigen. While protection was afforded to the liver, EQ alone caused severe damage to the kidney. Many changes were those of chronic glomerulonephrosis, such that EQ appeared to accelerate the ageing process. In addition, many hyperplastic and putative preneoplastic tubules were visible, suggesting that EQ may be exerting a carcinogenic effect in the kidney.