Yarita T, Nettesheim P
J Natl Cancer Inst. 1979 Feb;62(2):417-24.
F344 rats were exposed intragastrically to two different dose levels of N-nitrosoheptamethyleneimine (NHMI) resulting in a cumulative dose of either 225 or 450 mg/kg body weight. Tumor development was followed either in situ in the NHMI-exposed animals or in tracheas and esophagi from NHMI-exposed donors after these organs were grafted to isogeneic recipients. Tumor responses in situ and in organ grafts were compared. The results showed that the process of carcinogenesis is not disrupted by the transplantation procedure. The carcinogen dose-response relationship observed in situ was also seen in the transplanted organs. At the high carcinogen dose, the tumor incidence was 100% in situ and transplanted esophagi and 20% in tracheas in situ compared to 25% in tracheal transplants. At the low dose, the tumor incidence was 36% in the esophagi in situ compared to 100% in transplanted esophagi, which suggests a greater sensitivity of the transplant system to detect the carcinogenicity of NHMI. The proportion of carcinomas to papillomas was markedly higher in transplanted esophagi. The tracheal tumor response at both NHMI dose levels showed the same trend but was too low to allow any firm conclusions.
将F344大鼠经胃内给予两种不同剂量水平的N-亚硝基庚亚胺（NHMI），累积剂量分别为225或450mg/kg体重。在暴露于NHMI的动物体内原位观察肿瘤发展情况，或者在将暴露于NHMI的供体的气管和食管移植到同基因受体后，观察这些器官中的肿瘤发展情况。比较原位和器官移植中的肿瘤反应。结果表明，致癌过程不会因移植程序而中断。原位观察到的致癌物剂量反应关系在移植器官中也可见。在高致癌物剂量下，原位和移植食管的肿瘤发生率为100%，原位气管的肿瘤发生率为20%，而气管移植的肿瘤发生率为25%。在低剂量下，原位食管的肿瘤发生率为36%，而移植食管的肿瘤发生率为100%，这表明移植系统对检测NHMI致癌性的敏感性更高。移植食管中癌与乳头状瘤的比例明显更高。在两个NHMI剂量水平下，气管肿瘤反应呈现相同趋势，但发生率过低，无法得出任何确凿结论。
