Chang T H, Lee Y C, Lee K Y, Sun C H, Chang Y P
J Natl Cancer Inst. 1983 Jun;70(6):1067-75.
Albino rats (noninbred) were divided into 4 groups: 1) 56 control rats, 2) 40 rats fed 1 ml aspirin suspension (40 mg/ml) twice a week, 3) 20 rats given N-nitroso-N-methylnitroguanidine (MNNG) solution (250 micrograms/ml) to drink ad libitum, and 4) 40 rats given both aspirin and MNNG. In 18 months, there were no gastrointestinal tumors in groups 1 and 2, 8 cases of gastric tumors in group 3, and 37 cases of gastric tumors in group 4. Adenocarcinomas of the glandular stomach were found in 21 of 40 rats in group 4 but in only 4 of the 20 rats in group 3; the difference in incidence was significant. Histologic and electron microscopic examination of the epidermoid carcinomas and adenocarcinomas in group 4 showed no difference from such tumors induced by MNNG only. Hyperplasia of the forestomach mucosa and hyperplasia of the pyloric gland region of the glandular stomach in group 4 were more severe.
白化大鼠（非近亲繁殖）被分为4组：1）56只对照大鼠，2）40只大鼠每周两次喂食1毫升阿司匹林悬浮液（40毫克/毫升），3）20只大鼠自由饮用N-亚硝基-N-甲基亚硝基胍（MNNG）溶液（250微克/毫升），4）40只大鼠同时给予阿司匹林和MNNG。18个月后，第1组和第2组未出现胃肠道肿瘤，第3组有8例胃肿瘤，第4组有37例胃肿瘤。第4组40只大鼠中有21只发现腺胃腺癌，而第3组20只大鼠中只有4只；发病率差异显著。第4组表皮样癌和腺癌的组织学和电子显微镜检查显示与仅由MNNG诱导的此类肿瘤无差异。第4组前胃黏膜增生和腺胃幽门腺区增生更严重。
