The dimethylhydrazine induced colorectal tumours in rat - experimental colorectal carcinogenesis
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چکیده
The beginnings of the first animal model appreciated for its macroscopic and histological similarity to human colorectal carcinoma (CRC) extend to 1963, when Laqueur discovered that rats fed cycasin, a plant product, developed intestinal cancer. The active substance was identified and soon a similar compound, methylazoxymethanol acetate (MAMA) was synthesized that was more effective than the natural product. In 1970 Druckrey found that two chemicals structurally related to MAMA, dimethylhydrazine (DMH) and azoxymethane (AOM), were even more potent intestinal carcinogens.1 Today, DMH and its metabolite AOM are the agents widely used in experimental models of colorectal carcinogenesis in rodents. They are highly specific indirect colorectal carcinogens that induce the initiation and promotion steps of colorectal carcinogenesis yielding colorectal tumour lesions in a dose-dependent manner in rats, mice and hamsters.2-4 In rats they can produce colorectal tumour lesions in almost 100% of treated animals.4-8 Nevertheless, various strains of rats differ in susceptibility to these carcinogens.8-10 Radiol Oncol 2005; 39(1): 61-70.
منابع مشابه
Dimethylhydrazine model is not appropriate for evaluating effect of ethanol on colorectal cancer.
1,2 dimethylhydrazine (DMH) rat model has been proven to be a valuable animal model of colorectal cancer. Because of its morphological similarity to human colorectal cancer, DMH rat model was used to produce information in histology and biochemistry of tumours development as well as on factors that retard or enhance tumorigenesis. Nevertheless, it has been shown that DMH model has limitations, ...
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