Breneman J W, Briner J F, Ramsey M J, Director A, Tucker J D
Biology and Biotechnology Research Program, Lawrence Livermore National Laboratory, CA 94551, USA.
Food Chem Toxicol. 1996 Aug;34(8):717-24. doi: 10.1016/0278-6915(96)00043-9.
The primary food mutagens found in cooked meat are the heterocyclic aromatic amines, including 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx). High dose, acute exposures of MeIQx produce hepatic tumours in some mouse and rat strains. By assaying chromosome damage it may be possible to correlate aberrations with exposure to a mutagen. Whole chromosome painting by fluorescence in situ hybridization allows the rapid screening of metaphase chromosomes for rearrangements. This technique was applied to female mice (C57BL/6) chronically fed 100-400 ppms MeIQx for up to 6 months. Two tissues, blood and bone marrow, were screened with multicolour whole chromosome painting probes (1,2,3 and 8). The mice showed no outward signs of toxicity at any dose and very few chromosome aberrations were observed. A slight but significant increase in sister chromatid exchanges (SCE) was seen at 400 ppm in blood at 6 months. When MeIQx was removed from the diet for 1 month there was an apparent decline in SCEs only for animals previously given the 400 ppm diet.
熟肉中发现的主要食物诱变剂是杂环芳香胺，包括2-氨基-3,8-二甲基咪唑并[4,5-f]喹喔啉（MeIQx）。高剂量急性暴露于MeIQx会在一些小鼠和大鼠品系中诱发肝脏肿瘤。通过检测染色体损伤，有可能将畸变与诱变剂暴露相关联。荧光原位杂交进行的全染色体涂染可快速筛选中期染色体的重排情况。该技术应用于长期喂食100 - 400 ppm MeIQx长达6个月的雌性小鼠（C57BL/6）。使用多色全染色体涂染探针（1、2、3和8）对血液和骨髓这两种组织进行筛选。在任何剂量下，小鼠均未表现出明显的毒性迹象，仅观察到极少数染色体畸变。在6个月时，血液中400 ppm剂量组的姐妹染色单体交换（SCE）略有但显著增加。当从饮食中去除MeIQx 1个月后，仅先前喂食400 ppm饮食的动物的SCE明显下降。
