Abstract
The effect of green tea polyphenol fraction (GTP) on azoxymethane(AOM)‐induced colon carcino‐genesis was investigated in male Fischer rate. The rats were given AOM (7.4 mg/kg body weight) s.c. once a week for 10 weeks. A week after the treatment, they were divided into three groups: AOM‐control (26 rats), AOM‐GTP1 (26 rats) and AOM‐GTP2 (25 rats). AOM‐GTPl and AOM‐GTP2 groups respectively received 0.01 and 0.1% GTP in drinking water from week 11 to 26. AOM‐control group received tap water throughout this experiment. Autopsy on week 26 showed that tumor incidence and average numbers of tumors per rat in the AOM‐GTPl and AOM‐GTP2 groups were significantly lower than those of the AOM‐control group: 38.1% and 47.6% versus 77.3%; 0.6 and 0.7 versus 1.5. Thus, it was concluded that GTP inhibited the development of AOM‐indnced colon carcinogenesis. The inhibition by GTP did not show significant dose dependence.
Keywords: Colon carcinogenesis, Green tea, Azoxymethane, Polyphenol, (‐)‐Epigallocatechin gallate
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