Thompson H J, Meeker L D
Cancer Res. 1983 Apr;43(4):1628-9.
The efficacy of s.c. administration of 1-methyl-1-nitrosourea (MNU) for the induction of mammary carcinomas was compared with the i.v. method of carcinogen injection in female Sprague-Dawley rats. Group-housed animals fed a laboratory chow diet and distilled water ad libitum throughout the study were injected at 50 days of age with 50 mg MNU per kg body weight. The carcinogen was given either s.c. or i.v., via the jugular vein, to one of the two groups of 20 rats each. Animals were palpated for tumor detection weekly and necropsied 180 days after injection with the carcinogen. At the termination of the study, 180 days postcarcinogen, cancer incidences were similar, 95 versus 90% in animals given MNU either s.c. or i.v. with an average of 3.9 and 3.9 cancers per rat, respectively. Time of tumor appearances were essentially identical under both treatment conditions. Using either method of carcinogen administration resulted in the induction of approximately 2.4 times more carcinomas in the cervical-thoracic mammary glands than in the abdominal-inguinal glands with no differences observed in cancer occurrence in the left versus the right mammary gland chains. The data indicate that s.c. administration of MNU is as effective and specific in the induction of mammary carcinomas as is i.v. administration. The s.c. method has the advantage of being easier and faster to perform and permits reproducible treatment of large numbers of rats by a small technical staff.
在雌性斯普拉格-道利大鼠中，比较了皮下注射1-甲基-1-亚硝基脲（MNU）诱导乳腺癌的效果与静脉注射致癌剂的方法。在整个研究过程中，将成组饲养的动物随意喂食实验室普通饲料并饮用蒸馏水，在50日龄时给每组20只大鼠中的一组注射每千克体重50毫克的MNU。致癌剂通过皮下或静脉注射（经颈静脉）给予其中一组。每周对动物进行触诊以检测肿瘤，并在注射致癌剂180天后进行尸检。在研究结束时，即致癌剂注射后180天，皮下注射或静脉注射MNU的动物的癌症发生率相似，分别为95%和90%，每只大鼠平均患癌数分别为3.9个和3.9个。在两种治疗条件下，肿瘤出现的时间基本相同。无论采用哪种致癌剂给药方法，颈胸部乳腺诱导出的癌瘤数量均比腹腹股沟乳腺多约2.4倍，左右乳腺链中癌症的发生情况无差异。数据表明，皮下注射MNU在诱导乳腺癌方面与静脉注射一样有效且具有特异性。皮下注射方法具有操作更简便、速度更快的优点，并且允许少量技术人员对大量大鼠进行可重复的治疗。
