Khan A A, Coppock R W, Schuler M M, Florence L Z, Lillie L E, Mostrom M S
Environmental Toxicology, Alberta Environmental Centre, Canada.
Arch Environ Contam Toxicol. 1996 Mar;30(3):349-55. doi: 10.1007/BF00212293.
Crude oil pollution at drilling sites located within or in close proximity to agricultural pasture lands poses serious health risks to cattle raised on these lands. To investigate the clinical and systemic biochemical effects, cattle (8/group) were administered single oral doses of Pembina Cardium crude oil (PCCO) at 16.7, 33.4, and 67.4 g/kg, or water (control group) at 80 g/kg. Cattle exposed to PCCO showed dose-dependent clinical effects. At the lowest dosage, PCCO caused transient and minimal clinical effects; however, high dosages caused varied clinical signs which included tremors, nystagmus, vomiting, and pulmonary distress. On posttreatment day 7 or 30, four cattle from each treatment group were sacrificed and biochemical parameters were assayed in liver, lungs, and kidney cortex. In cattle monitored on posttreatment day 7, the PCCO-treated groups showed marked alterations from the control group in hepatic cytochrome P-450 (P-450), and in aryl hydrocarbon hydroxylase (AHH) and 7-ethoxycoumarin-O-deethylase (ECOD) activities of these tissues. Administration of PCCO caused significant increases (> 100%) in hepatic P-450, but produced variable effects on AHH and ECOD activities in each tissue. The activity of AHH was increased in all tissues; however, the effect was highest in kidney cortex (> 5000%), followed by liver (> 500%) and lungs (> 250%). The activity of ECOD was altered in a differential manner. It was either increased markedly (>1300%) in kidney cortex or increased slightly (20-30%) in liver, but decreased (> 80%) in lungs. The activities of respiratory chain enzymes (succinate-cytochrome c reductase, NADH-cytochrome c reductase and cytochrome oxidase), or NADPH-cytochrome c reductase and glutathione transferase were not changed significantly in any tissues. The alterations in P-450, AHH, and ECOD observed on day 7 were markedly reversed in cattle examined on day 30 posttreatment, indicating a recovery from induced changes. Studies in vitro with hepatic microsomal preparations from day 7 posttreatment groups showed that increases in AHH and ECOD activity in PCCO-treated cattle were due to induction of new isoforms of P-450, as evidenced by (1) the appearance of a 448-nm spectral peak, and (2) differential inhibitory effects of metyrapone and 7,8-benzoflavone on AHH and ECOD activities.
位于农业牧场范围内或附近的钻井现场的原油污染，对在这些土地上饲养的牛群构成严重的健康风险。为了研究临床和全身生化效应，将牛（每组8头）分别以16.7、33.4和67.4 g/kg的剂量单次口服彭比纳心原油（PCCO），或以80 g/kg的剂量口服水（对照组）。接触PCCO的牛表现出剂量依赖性的临床效应。在最低剂量下，PCCO引起短暂且轻微的临床效应；然而，高剂量会导致各种临床症状，包括震颤、眼球震颤、呕吐和肺部窘迫。在治疗后第7天或第30天，对每个治疗组的4头牛实施安乐死，并测定肝脏、肺和肾皮质中的生化参数。在治疗后第7天监测的牛中，PCCO处理组在肝细胞色素P-450（P-450）以及这些组织的芳烃羟化酶（AHH）和7-乙氧基香豆素-O-脱乙基酶（ECOD）活性方面与对照组相比有明显改变。给予PCCO导致肝脏P-450显著增加（>100%），但对每个组织中AHH和ECOD活性产生不同影响。所有组织中AHH活性均增加；然而，肾皮质中的影响最大（>5000%），其次是肝脏（>500%）和肺（>250%）。ECOD活性以不同方式改变。它在肾皮质中显著增加（>1300%），在肝脏中略有增加（20 - 30%），但在肺中降低（>80%）。任何组织中的呼吸链酶（琥珀酸 - 细胞色素c还原酶、NADH - 细胞色素c还原酶和细胞色素氧化酶）、NADPH - 细胞色素c还原酶和谷胱甘肽转移酶活性均未发生显著变化。在治疗后第30天检查的牛中，治疗后第7天观察到的P-450、AHH和ECOD的改变明显逆转，表明诱导变化已恢复。对治疗后第7天组的肝脏微粒体制剂进行的体外研究表明，PCCO处理的牛中AHH和ECOD活性的增加是由于诱导了新的P-450同工型，这由以下两点证明：（1）出现448 nm的光谱峰，以及（2）美替拉酮和7,8 - 苯并黄酮对AHH和ECOD活性的不同抑制作用。
