Welsch C W, Brown C K, Goodrich-Smith M, Van J, Denenberg B, Anderson T M, Brooks C L
J Natl Cancer Inst. 1979 Nov;63(5):1211-4.
One hundred sixty-eight female Lewis rats were treated intragastrically with 10 mg 7,12-dimethylbenz[a]anthracene at 56 and 63 days of age. Pituitary prolactin secretion was suppressed in one-half of these rats by daily sc administrations of 2-bromoergocryptine mesylate (CB-154; 0.4 mg/100 g body wt) from 29 to 90 days of age (series 1) and from 90 to 140 days of age (series 2). Treatment with CB-154 was initiated prior to the onset of palpable mammary carcinomas. Control rats were given injections of saline. Inguinal mammary glands were excised from 10 control and 10 CB-154-treated rats at the cessation of saline and CB-154 treatments and examined for hyperplastic nodules (HN). The remaining rats were palpated weekly for mammary carcinomas (MC) and killed at 200 days of age. Mean number of HN per rat, mean number of MC per rat, and percent of rats with MC were, respectively: series 1--controls, 0.6, 1.5, and 68; CB-154 treatment, 0.5, 1.1, and 62; series 2--controls, 10.4, 2.0, and 94; CB-154 treatment, 5.1, 1.1, and 56. The number of HN and MC was only slightly reduced in rats when prolactin was suppressed during carcinogen treatment (series 1) but markedly reduced when prolactin was suppressed after carcinogen treatment (series 2). These results provide evidence that prolactin is involved in the early development of mammary dysplasias in the carcinogen-treated female Lewis rat.
168只雌性Lewis大鼠在56日龄和63日龄时经口给予10毫克7,12-二甲基苯并[a]蒽。其中一半大鼠从29日龄至90日龄（第1组）以及从90日龄至140日龄（第2组）每天皮下注射甲磺酸溴隐亭（CB-154；0.4毫克/100克体重）以抑制垂体催乳素分泌。CB-154治疗在可触及的乳腺癌出现之前开始。对照大鼠注射生理盐水。在停止生理盐水和CB-154治疗后，从10只对照大鼠和10只经CB-154治疗的大鼠中切除腹股沟乳腺，检查是否有增生性结节（HN）。其余大鼠每周触诊检查乳腺癌（MC），并在200日龄时处死。每只大鼠的HN平均数量、每只大鼠的MC平均数量以及有MC的大鼠百分比分别为：第1组——对照，0.6、1.5和68；CB-154治疗组，0.5、1.1和62；第2组——对照，10.4、2.0和94；CB-154治疗组，5.1、1.1和56。在致癌物处理期间抑制催乳素时，大鼠的HN和MC数量仅略有减少（第1组），但在致癌物处理后抑制催乳素时则明显减少（第2组）。这些结果证明催乳素参与了致癌物处理的雌性Lewis大鼠乳腺发育异常的早期过程。
