Hirose M, Uwagawa S, Ozaki K, Takaba K, Ito N
First Department of Pathology, Nagoya City University Medical School, Japan.
Carcinogenesis. 1991 Oct;12(10):1773-6. doi: 10.1093/carcin/12.10.1773.
The effects of butylated hydroxyanisole (BHA) pretreatment on subsequent low dose N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) or N,N-dibutylnitrosamine (DBN) treatment on forestomach or esophageal carcinogenesis were investigated in male F344 rats. Groups of animals were pretreated with 2% BHA or basal diet alone for 24 weeks and then were given 20 mg/kg body wt MNNG once every 2 weeks, 0.025% DBN in drinking water continuously or basal diet alone for the subsequent 24 weeks. Further groups of rats were similarly treated with BHA or basal diet alone for 24 weeks, placed on basal diet for the next 24 weeks and then treated with MNNG, DBN or basal diet alone for the subsequent 24 weeks. Animals were killed 48 or 72 weeks after the beginning of the experiment. Histopathological examination showed that the incidence of forestomach tumors was not significantly affected by the BHA pretreatment in the MNNG-treated groups. On the other hand, the incidence of esophageal squamous cell carcinomas was lower in the group pretreated with BHA followed by DBN than in that treated with basal diet followed by DBN (48 week experiment). There was no significant difference in esophageal tumor incidence in the 72 week experiment. The results thus indicate that continuous treatment with 2% BHA for 24 weeks does not exert initiating activity on forestomach and esophageal epithelia.
在雄性F344大鼠中，研究了丁基羟基茴香醚（BHA）预处理对随后低剂量N-甲基-N'-硝基-N-亚硝基胍（MNNG）或N，N-二丁基亚硝胺（DBN）处理对前胃或食管癌发生的影响。将动物分组，分别用2%BHA或仅用基础饲料预处理24周，然后每2周给予20mg/kg体重的MNNG一次，在随后的24周内持续给予饮用水中0.025%的DBN或仅给予基础饲料。另外几组大鼠同样用BHA或仅用基础饲料预处理24周，接下来24周给予基础饲料，然后在随后的24周内用MNNG、DBN或仅用基础饲料处理。在实验开始48或72周后处死动物。组织病理学检查显示，在MNNG处理组中，BHA预处理对前胃肿瘤的发生率没有显著影响。另一方面，在先用BHA预处理后再用DBN处理的组中，食管鳞状细胞癌的发生率低于先用基础饲料预处理后再用DBN处理的组（48周实验）。在72周实验中，食管肿瘤发生率没有显著差异。因此，结果表明，连续24周用2%BHA处理对前胃和食管上皮没有启动活性。
