Effects of multiple pituitary homografts or progesterone on 7,12-dimethylbenz[a]anthracene-induced mammary tumors in rats.
Effects of multiple pituitary homografts or progesterone on 7,12-dimethylbenz[a]anthracene-induced mammary tumors in rats.
复制标题
多个垂体同种移植物或黄体酮对 7,12-二甲基苯并[a]蒽诱导的大鼠乳腺肿瘤的影响。
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发表时间：
1968
期刊：
影响因子：
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通讯作者：
J. Meites
中科院分区：
文献类型：
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作者：
C. Welsch;J. Clemens;J. Meites
本研究评价了分泌催乳素的垂体同种移植物和孕酮对随后用712-二甲基苯并[α]蒽（DMBA）处理的雌性大鼠乳腺肿瘤诱导的影响。将未成熟雌性SD大鼠分为5组：1组为正常对照组; 2组为卵巢切除组; 3组为正常垂体和4个垂体同种移植物组; 4组为卵巢切除和4个垂体同种移植物组; 5组为正常垂体和每日注射孕酮4 mg组。在25日龄时进行睾丸移植和/或卵巢切除术。从30日龄开始注射Progesterone，并连续注射40天。在55日龄时，对所有动物给予5 mg DMBA的单次静脉内剂量。在研究结束时，肿瘤发生率百分比、平均肿瘤数/大鼠和平均肿瘤总重量/大鼠（g）为：组1 100% 12.2 +或-1.2 16. 2+或-3.5;组2 0;组3 73% 4.7 +或-1.3 5. 4+或-2.0;组4 0;第5组79% 3.3 ± 0.7 5.9 ± 4.6。与完整对照组相比，携带4个垂体同种移植物的完整大鼠和注射孕酮的完整大鼠的肿瘤百分比、平均肿瘤数/大鼠和平均肿瘤总重量/大鼠均显着降低。催乳素分泌垂体同种移植物的抑制作用似乎至少部分通过卵巢介导，因为每天注射孕酮导致乳腺肿瘤发生的抑制作用相当。这些数据表明，催乳素和/或孕酮通过刺激乳腺的生长和发育生长抑制DMBA诱导的乳腺肿瘤发生，如果给予足够的致癌物治疗之前。（作者）
This investigation evaluates the effects of prolactin-secreting pituitary homografts and progesterone on the induction of mamary tumors in female rats subsequently treated with 712-dimethylbenz[alpha]anthracene (DMBA). Immature female Sprague-Dawley rats were divided into 5 groups: group 1 intact controls; group 2 ovariectomized; group 3 intact and 4 pituitary homografts; group 4 ovariectomized and 4 pituitary homografts; and group 5 intact and given injection of 4 mg progesterone daily. Pituitary transplantation and/or ovariectomy were performed at age 25 days. Progesterone was injected beginning at 30 days of age and continued for 40 consecutive days. At age 55 days all animals were given a single intravenous dose of 5 mg DMBA. At the end of the study the percent of tumor incidence average number of tumors/rat and average total weight of tumors/rat (g) were: group 1 100% 12.2 +or- 1.2 16.2 +or- 3.5; group 2 0; group 3 73% 4.7 +or- 1.3 5.4 +or- 2.0; group 4 0; and group 5 79% 3.3 +or- 0.7 5.9 +or- 4.6. Percentage of rats with tumors average number of tumors/rat and average total weight of tumors/rat were significantly decreased in intact rats bearing 4 pituitary homografts and in intact rats given injections of progesterone as compared to the intact controls. The inhibitory effect of the prolactin-secreting pituitary homografts appears to be mediated at least in part through the ovary since daily injections of progesterone resulted in a comparable inhibition of mammary tumorigenesis. These data indicate that prolactin and/or progesterone by stimulating growth and development growth of the mammary gland inhibit DMBA-induced mammary tumorigenesis if given sufficiently prior to carcinogen treatment. (authors)