Effect of Catechol Estrogens on Rat Mammary Tumors1
نویسنده
چکیده
The effect of 1,3,5(i 0)-estratriene-3,1 6a,i 7f@-triol(estriol), i ,3,5(i O)-estratriene-2,3-diol-i 7-one (2-hydroxyestrone), and 1,3,5(i 0)-estratriene-2,3,i 7$-triol (2-hydroxyestradiol) on the growth of dirnethylbenz(a)anthracene-induced mammary tumor and of R3230AC-transplantable mammary tumor was corn pared with that produced by estradiol benzoate treatment. Estriol showed minimal inhibition of tumor growth in dirnethyl benz(a)anthracene-induced tumor and no effect on R3230AC tumor while 2-hydroxyestrone showed no effect of tumor inhi bition. On the other hand, 2-hydroxyestradiol showed appre ciable inhibition of tumor growth in both tumors studied. That 2-hydroxyestradiol has been found to bind to estrogen recep tors in mammary tumors and is uterotropic suggests that the inhibition of tumor growth by 2-hydroxyestradiol may be similar to the mechanism of inhibition of mammary tumors by high concentrations of estradiol.
منابع مشابه
Effect of catechol estrogens on rat mammary tumors.
The effect of 1,3,5(10)-estratriene-3, 16 alpha, 17 beta-triol (estriol), 1, 3, 5(10)-estratriene-2,3-diol-17-one (2-hydroxyestrone), and 1,3,5(10)-estratriene-2,3,17 beta-triol (2-hydroxyestradiol) on the growth of dimethylbenz(a)anthracene-induced mammary tumor and of R3230AC-transplantable mammary tumor was compared with that produced by estradiol benzoate treatment. Estriol showed minimal i...
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