Both rat and mouse and other rodents are used for uterotrophic assay. These models are used to test  toxicologically relevant in vivo estrogenicity of estrogens.Vaginal opening is shown to be a useful, but nondefinitive, adjunct to the uterotrophic assay. The ability of test chemicals to reduce or abolish the uterotrophic response of estradiol is suggested to provide a useful extension of the uterotrophic assay for the purpose of detecting antiestrogens.  17beta-Desoxyestradiol and estradiol are also tested in the uterotrophic assay

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