Bird R P, Medline A, Furrer R, Bruce W R
Carcinogenesis. 1985 Jul;6(7):1063-6. doi: 10.1093/carcin/6.7.1063.
C57BL/6J mice were given a gavage of from 0.1 to 0.4 ml beef tallow (BT) or corn oil (CO). The damaging effect of the orally administered fat boluses could be visualized 2-4 h later by instilling the excised animal colons with Trypan blue, a vital dye that stains non-viable cells. Microscopic examination of sections prepared at these times revealed that the tall columnar cells on the surface of the normal epithelium were replaced with cells demonstrating flattened, pleomorphic, pyknotic and fragmented nuclei. This phenomenon was quantitated by scoring 100 intercrypt epithelial zones between well-defined crypts. The maximum damage, affecting 25-45% of the epithelial zones, was seen at 2-4 h after treatment with 0.4 ml of BT or CO and the epithelium appeared normal with less than 10% damage at 12 h. The mitotic activity in the colonic crypts was unchanged up to 8 h and then showed a marked increase of 2- to 3-fold at 12-16 h. The severity of the epithelial damage and ensuing mitogenic response was related to the size of the fat bolus. These observations would suggest that the effects of any carcinogens present in the diet or formed in the feces could be enhanced if a fatty meal results in colonic damage and subsequent cell proliferation as we have observed in mice.
给C57BL/6J小鼠灌胃0.1至0.4毫升牛脂（BT）或玉米油（CO）。口服脂肪团的损伤作用可在2至4小时后通过向切除的动物结肠中注入台盼蓝来观察，台盼蓝是一种对非存活细胞染色的活性染料。对此时制备的切片进行显微镜检查发现，正常上皮表面的高柱状细胞被细胞核扁平、多形、固缩和破碎的细胞所取代。通过对明确隐窝之间的100个隐窝间上皮区域进行评分来对这一现象进行量化。在用0.4毫升BT或CO处理后2至4小时，观察到最大损伤，影响25%至45%的上皮区域，而在12小时时上皮损伤小于10%，看起来正常。结肠隐窝中的有丝分裂活性在8小时内未发生变化，然后在12至16小时时显著增加2至3倍。上皮损伤的严重程度和随后的促有丝分裂反应与脂肪团的大小有关。这些观察结果表明，如果如我们在小鼠中所观察到的那样，高脂肪餐导致结肠损伤和随后的细胞增殖，那么饮食中存在的或粪便中形成的任何致癌物的影响可能会增强。
