Hirakawa T, Nemoto N, Yamada M A, Takayama S
Chem Biol Interact. 1979 May;25(2-3):189-95. doi: 10.1016/0009-2797(79)90045-0.
The rate of metabolism of benzo[a]pyrene (BP) and changes in related enzyme activities in cultured hamster embryo cells during successive subculture were studied. The activity of aryl hydrocarbon hydroxylase (AHH) was the highest when embryo cells were first dispersed in tissue culture flasks and decreased during subsequent passages. On the other hand, UDP-glucuronyl transferase activity increased gradually during successive subculture. Treatment of the cells with 13 nmol/ml of benz[a]anthracene (BA) for 24 h increased the activity of AHH but not that of UDP-glucuronyl transferase. The metabolism of BP was measured in cells of the passages 1, 3 and 7; metabolism of BP was most efficient in cells in passage 3 and their formation of glucuronic acid conjugates of BP, one of the major metabolites found in the medium, was 3- and 10-fold more than those of cells in passages 1 and 7, respectively. Analysis of BP-metabolites extracted from the medium with ethylacetate showed that the main metabolites were 9,10-diol and 7,8-diol. Phenols and quinones were released by treatment of the medium with beta- glucuronidase and their amounts were larger than those of diols at all passages. These results show that in hamster embryo cells in early passage, BP is metabolized to conjugates of phenols with glucuronic acid.
研究了连续传代培养的仓鼠胚胎细胞中苯并[a]芘（BP）的代谢速率及相关酶活性的变化。当胚胎细胞首次分散于组织培养瓶中时，芳烃羟化酶（AHH）活性最高，随后传代过程中活性降低。另一方面，尿苷二磷酸葡萄糖醛酸基转移酶活性在连续传代培养过程中逐渐增加。用13 nmol/ml苯并[a]蒽（BA）处理细胞24小时可增加AHH活性，但不增加尿苷二磷酸葡萄糖醛酸基转移酶活性。在第1、3和7代细胞中测定了BP的代谢；BP在第3代细胞中的代谢效率最高，其形成的BP葡萄糖醛酸共轭物（培养基中发现的主要代谢产物之一）分别比第1代和第7代细胞中的多3倍和10倍。用乙酸乙酯从培养基中提取BP代谢产物进行分析，结果表明主要代谢产物为9,10-二醇和7,8-二醇。用β-葡萄糖醛酸酶处理培养基可释放出酚类和醌类物质，在所有传代中其含量均高于二醇类。这些结果表明，在传代早期的仓鼠胚胎细胞中，BP被代谢为酚类与葡萄糖醛酸的共轭物。
