代谢
邻苯基苯酚(OPP)在雄性B6C3F1小鼠中的吸收情况良好,单次口服剂量为15或800毫克/千克时,动物在0-48小时内的尿液中分别回收了84%和98%的放射性物质。雌性和雄性F344大鼠也表现出高吸收和快速消除的特点,单次口服剂量(27-28毫克/千克)的86%和89%在24小时内通过尿液排出。OPP在人类志愿者皮肤暴露8小时(0.006毫克/千克)后也迅速消除,48小时内尿液中有99%的吸收剂量。在所有三种物种中,低剂量的OPP硫酸化被发现是其主要的代谢途径,分别占雄性小鼠(15毫克/千克,口服)、雄性大鼠(28毫克/千克,口服)和男性志愿者(0.006毫克/千克,皮肤)尿液中放射性活性的57%、82%和69%。OPP-葡萄糖醛酸苷在所有物种中也存在,分别代表低剂量组小鼠、大鼠和志愿者尿液中总代谢物中的29%、7%和4%。在单次剂量研究中,2-苯基对苯二酚(PHQ)的共轭物在鼠、大鼠和人类中分别占剂量的12%、5%和15%。在任何物种中几乎没有发现自由的OPP。在小鼠、大鼠或人类中没有发现自由的PHQ或PBQ(检测限为0.1-0.6%)。在大鼠和人类中发现了一种新的代谢物,即2,4'-二羟基联苯的硫酸共轭物,在低剂量中分别占3%和13%。在小鼠中,母体OPP的共轭作用随剂量依赖性变化,表明硫酸化途径达到饱和。小鼠中总PHQ的剂量依赖性增加也观察到。这项研究旨在阐明大鼠和小鼠之间OPP致癌潜力差异的机制基础。然而,这两种物种在OPP代谢上的微小差异似乎无法解释小鼠和大鼠在膀胱毒性和肿瘤反应上的差异。
Ortho-phenylphenol (OPP) was well absorbed in the male B6C3F1 mouse, with 84 and 98% of the administered radioactivity recovered in the 0-48-hr urine of animals administered a single oral dose of 15 or 800 mg/kg respectively. High absorption and rapid elimination were also seen in the female and male F344 rat with 86 and 89% respectively of a single oral dose (27-28 mg/kg) found in the urine in 24 hr. OPP was also rapidly eliminated from human volunteers following dermal exposure for 8 hr (0.006 mg/kg), with 99% of the absorbed dose in the urine in 48 hr.. Sulfation of OPP was found to be the major metabolic pathway at low doses in all three species, accounting for 57, 82 and 69% of the urinary radioactivity in the male mouse (15 mg/kg, po), male rat (28 mg/kg, po) and male human volunteers (0.006 mg/kg, dermal). OPP-glucuronide was also present in all species, representing 29, 7 and 4% of the total urinary metabolites in the low dose groups of mouse, rat and human volunteers respectively. Conjugates of 2-phenylhydroquinone (PHQ) in these single-dose studies accounted for 12, 5 and 15% of the dose in mouse, rat and human, respectively. Little or no free OPP was found in any species. No free PHQ or PBQ was found in the mouse, rat or human (LOD = 0.1-0.6%). A novel metabolite, the sulfate conjugate of 2,4'-dihydroxybiphenyl, was identified in rat and man, comprising 3 and 13% of the low dose respectively. Dose-dependent shifts in metabolism were seen in the mouse for conjugation of parent OPP, indicating saturation of the sulfation pathway. Dose-dependent increases in total PHQ were also observed in mouse. This study was initiated to elucidate a mechanistic basis for the difference in carcinogenic potential for OPP between rat and mouse. However, the minor differences seen in the metabolism of OPP in these two species do not appear to account for the differences in urinary bladder toxicity and tumor response between mouse and rat.
来源:Hazardous Substances Data Bank (HSDB)