Antiestrogens Archives - Revista Brasileira de Ginecologia e Obstetrícia
Summary
Rev Bras Ginecol Obstet. 2000;22(1):33-36
DOI 10.1590/S0100-72032000000100006
Purpose: to evaluate the morphologic and morphometric alterations produced by tamoxifen and conjugated estrogens in the mammary epithelium of rats in persistent estrus. Methods: thirty-three adult female rats in persistent estrus induced with 1.25 mg testosterone propionate were divided at random into three groups: GI -- which received only water, control group (n = 12); GII -- treated with 500 mug tamoxifen daily (n = 10); GIII -- treated with 30 mug conjugated estrogens per day (n = 11). The first inguinal-abdominal pair of mammary glands of the animals was extirpated and processed for morphologic and morphometric study. Data were analyzed statistically by the Kruskal-Wallis rank analysis of variance (p < 0.05). Results: the morphologic study revealed signs of epithelial atrophy and the morphometric study showed a statistically significant reduction in the mean number of ducts and alveoli in groups II (10.1 and 1.9, respectively) and III (11.1 and 3.5, respectively) compared to group I (25.0 and 6.6, respectively). There was no significant difference between groups II and III. Conclusions: the results of this study indicate that tamoxifen as well as conjugated estrogens at the tested doses produced mammary epithelial atrophy in rats in persistent estrus.
Summary
Rev Bras Ginecol Obstet. 2000;22(1):33-36
DOI 10.1590/S0100-72032000000100006
Purpose: to evaluate the morphologic and morphometric alterations produced by tamoxifen and conjugated estrogens in the mammary epithelium of rats in persistent estrus. Methods: thirty-three adult female rats in persistent estrus induced with 1.25 mg testosterone propionate were divided at random into three groups: GI -- which received only water, control group (n = 12); GII -- treated with 500 mug tamoxifen daily (n = 10); GIII -- treated with 30 mug conjugated estrogens per day (n = 11). The first inguinal-abdominal pair of mammary glands of the animals was extirpated and processed for morphologic and morphometric study. Data were analyzed statistically by the Kruskal-Wallis rank analysis of variance (p < 0.05). Results: the morphologic study revealed signs of epithelial atrophy and the morphometric study showed a statistically significant reduction in the mean number of ducts and alveoli in groups II (10.1 and 1.9, respectively) and III (11.1 and 3.5, respectively) compared to group I (25.0 and 6.6, respectively). There was no significant difference between groups II and III. Conclusions: the results of this study indicate that tamoxifen as well as conjugated estrogens at the tested doses produced mammary epithelial atrophy in rats in persistent estrus.
Summary
Rev Bras Ginecol Obstet. 2000;22(7):429-433
DOI 10.1590/S0100-72032000000700005
Purpose: to study the monoclonal antibody MIB-1 in the normal breast epithelium adjacent to a fibroadenoma in women in the luteal phase of the menstrual cycle treated with tamoxifen. Patients and methods: the proliferative activity of the mammary epithelium adjacent to the fibroadenoma was studied by immunohistochemistry based on immunoexpression of the monoclonal antibody MIB-1. The study was randomized and double blind and was conducted on 44 women with fibroadenomas, divided into 3 groups: A (n = 16; placebo), B (n = 15; tamoxifen, 10 mg), and C (n = 13; tamoxifen, 20 mg). Tamoxifen was administered for 22 days starting on the 2nd day of the menstrual cycle and a biopsy was taken on the 23rd day. Results: the mean percentage of stained nuclei per 1000 cells was 9.2 in group A, 4.5 in group B, and 3.2 in group C. Fisher's test revealed that tamoxifen significantly reduced the immunoexpression of MIB-1 at the doses of 10 and 20 mg compared to the placebo group (p<0.0001), with no significant differences between doses in terms of proliferative activity (p = 0.21). Conclusion: we conclude that tamoxifen significantly reduced the proliferative activity of the mammary epithelium at the doses of 10 and 20 mg/day.
Summary
Rev Bras Ginecol Obstet. 2000;22(7):429-433
DOI 10.1590/S0100-72032000000700005
Purpose: to study the monoclonal antibody MIB-1 in the normal breast epithelium adjacent to a fibroadenoma in women in the luteal phase of the menstrual cycle treated with tamoxifen. Patients and methods: the proliferative activity of the mammary epithelium adjacent to the fibroadenoma was studied by immunohistochemistry based on immunoexpression of the monoclonal antibody MIB-1. The study was randomized and double blind and was conducted on 44 women with fibroadenomas, divided into 3 groups: A (n = 16; placebo), B (n = 15; tamoxifen, 10 mg), and C (n = 13; tamoxifen, 20 mg). Tamoxifen was administered for 22 days starting on the 2nd day of the menstrual cycle and a biopsy was taken on the 23rd day. Results: the mean percentage of stained nuclei per 1000 cells was 9.2 in group A, 4.5 in group B, and 3.2 in group C. Fisher's test revealed that tamoxifen significantly reduced the immunoexpression of MIB-1 at the doses of 10 and 20 mg compared to the placebo group (p<0.0001), with no significant differences between doses in terms of proliferative activity (p = 0.21). Conclusion: we conclude that tamoxifen significantly reduced the proliferative activity of the mammary epithelium at the doses of 10 and 20 mg/day.
