Singletary K W, McNary M Q, Odoms A M, Nelshoppen J, Wallig M A
Division of Foods and Nutrition, University of Illinois, Urbana-Champaign 61801.
Nutr Cancer. 1991;16(1):13-23. doi: 10.1080/01635589109514136.
In this study, we report that chronic ethanol intake at 20% of calories can enhance the initiation stage and at 15% of calories can enhance the promotion stage of 7,12-dimethylbenz[a]anthracene (DMBA)-induced mammary tumorigenesis in female Sprague-Dawley rats. Ethanol consumption at 20% of calories by female rats from 25 to 53 days of age was associated with a significant increase in terminal end bud (TEB) structures and a significant decrease in alveolar bud structures of the normal mammary gland. In addition to changes in mammary gland morphology, ethanol consumption at 20% of calories also was associated with a significant increase in incorporation of [3H]thymidine into mammary DNA and a significant increase in the DNA-labeling index of mammary TEB. Therefore, specific ethanol intakes can enhance DMBA-induced mammary tumorigenesis. The enhancement of the initiation stage partly may be explained by alterations in the structural development of the normal rat mammary gland that increase susceptibility to chemically induced mammary tumorigenesis.
在本研究中，我们报告称，雌性斯普拉格-道利大鼠摄入占卡路里20%的慢性乙醇可增强7,12-二甲基苯并[a]蒽（DMBA）诱导的乳腺肿瘤发生的起始阶段，而摄入占卡路里15%的乙醇可增强促进阶段。25至53日龄的雌性大鼠摄入占卡路里20%的乙醇，与正常乳腺的终末芽（TEB）结构显著增加以及肺泡芽结构显著减少有关。除了乳腺形态的变化外，摄入占卡路里20%的乙醇还与[3H]胸腺嘧啶核苷掺入乳腺DNA显著增加以及乳腺TEB的DNA标记指数显著增加有关。因此，特定的乙醇摄入量可增强DMBA诱导的乳腺肿瘤发生。起始阶段的增强部分可能是由于正常大鼠乳腺结构发育的改变，从而增加了对化学诱导的乳腺肿瘤发生的易感性。
