Study of Rats' Mammary Precancer models-induced by DMBA combined estrogen and progesterone

Objective: To explore using 7, 12-Dimethylbenz[a] anthracen(DMBA) combined estrogen and progesterone induce Rats Model of Mammary Precancer, and investigate the inhibitory effect of tamoxifen ointment. Methods: 30 virginal female SD rats were randomly allocated into three groups, A: Blank control group (10); B: DMBA+hormones group (10); C: TAM group (10). The general morphology and pathology were observed when the rats were executed after 60 days. Results: The incidence of premalignant breast disease in model group B was 87.5%, while group C was 47.5%. Group B was significantly higher than group C (P<;0.01). Conclusion: DMBA+hormones method is a method to establish Rats Model of Mammary Precancer. Tamoxifen could effectively prevent the occurrence of DMBA+hormones induced breast precancer in rats.