The synergistic effect of 1-hydroxyanthraquinone on methylazoxymethanol acetate-induced carcinogenesis in rats

The synergistic potential of 1-hydroxyanthraquinone (1-HA) on methylazoxymethanol (MAM) acetate-induced carcinogenesis was investigated in rats. A total of 154 inbred ACI/N rats (73 males and 81 females), six weeks old at the start of the experiment, were divided into four groups: group 1 was given i.p. injections of MAM acetate (25 mg/kg body wt), once per week for 2 weeks and then fed the diet containing 1% 1-HA for 42 weeks; group 2 received MAM acetate and was kept on the basal diet alone; group 3 was given 1-HA containing diet alone as for group 1; group 4 was treated as a control. At the termination of the experiment, the carcinogenic effect of MAM acetate and 1-HA in the large bowel or liver exceeded the sum of effects when given alone, indicating that the two chemicals act synergistically in the carcinogenesis of these organs.