Kiyohara C, Hirohata T
Department of Public Health, Faculty of Medicine, Kyushu University, Fukuoka-shi, Japan.
Toxicol Lett. 1993 Feb;66(2):199-207. doi: 10.1016/0378-4274(93)90095-f.
In vivo administration of 3-methylcholanthrene (MC) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) produced much higher hepatic microsomal aryl hydrocarbon hydroxylase (AHH) induction than 7,8-benzoflavone (7,8-BF) in both aromatic hydrocarbon (Ah)-responsive and nonresponsive strains of mice. Simultaneous treatment or pre-treatment with 7,8-BF produced an inhibitory effect on AHH induction by MC or TCDD (i.e., the degrees of the inhibition, with TCDD, were 28% in the Ah-responsive strain C57BL/6N (C57) mice and 45% in the nonresponsive strain DDD;Qdj (DDD) mice). However, posttreatment with 7,8-BF was inclined to promote the induction of AHH by MC or TCDD (i.e., the degrees of the enhancement, with MC, were 15% in C57 mice and 45% in DDD mice). These results may suggest that the inhibitory effect of 7,8-BF in vivo is limited not to the combination of AHH inducer (MC or TCDD) but to its application of timing or Ah responsiveness.
在对芳烃（Ah）反应性和无反应性小鼠品系中，体内给予3-甲基胆蒽（MC）和2,3,7,8-四氯二苯并对二恶英（TCDD）所产生的肝微粒体芳烃羟化酶（AHH）诱导作用，比给予7,8-苯并黄酮（7,8-BF）所产生的诱导作用高得多。同时用7,8-BF处理或预处理对MC或TCDD诱导的AHH产生抑制作用（即，对于TCDD，在Ah反应性品系C57BL/6N（C57）小鼠中的抑制程度为28%，在无反应性品系DDD;Qdj（DDD）小鼠中的抑制程度为45%）。然而，用7,8-BF进行后处理倾向于促进MC或TCDD对AHH的诱导作用（即，对于MC，在C57小鼠中的增强程度为15%，在DDD小鼠中的增强程度为45%）。这些结果可能表明，7,8-BF在体内的抑制作用不仅限于AHH诱导剂（MC或TCDD）的组合，还与其应用时机或Ah反应性有关。
