Otto D M, Moon T W
Ottawa-Carleton Institute of Biology, Department Biology, University of Ottawa, Ontario, Canada.
Pharmacol Toxicol. 1995 Oct;77(4):281-7. doi: 10.1111/j.1600-0773.1995.tb01028.x.
Polychlorinated biphenyls are known to cause induction in cytochrome P450-dependent monooxygenase activities and alteration in the antioxidant defense of mammals. To determine whether similar detoxication processes are activated in rainbow trout (Oncorhynchus mykiss), we investigated P450-dependent enzyme activities, antioxidant enzymes and glutathione status (reduced and oxidized glutathione, GSH and GSSG) in this species injected intraperitoneally with 3,3',4,4'-tetrachlorobiphenyl at 5 mg/kg body weight 6 weeks post injection. Ethoxyresorufin O-deethylase activities increased 11- and 40-fold in liver and kidney. UDPglucuronosyltransferase activities were 2- and 5-fold higher in these organs, while glutathione S-transferase activity was enhanced greater than 2-fold in liver of tetrachlorobiphenyl injected trout in comparison with controls. Glutathione peroxidase activities were increased in liver and white muscle of dosed fish. Tetrachlorobiphenyl exposure resulted in a significant increase in glutathione reductase activities, with 7-fold enhancement in liver and significantly elevated activities in kidney, red and white muscles. Similarly, cytosolic superoxide dismutase and catalase activities were increased in white muscle of injected trout. Tetrachlorobiphenyl exposure significantly increased GSH concentrations in liver and kidney, while GSSG levels were increased in liver and blood plasma. These changes, however, did not modify the GSSG/GSH ratios in these tissues. Overall, these results imply a major tetrachlorobiphenyl effect on GSH status and antioxidant enzymes in trout tissues and identify white muscle along with liver and kidney as important tissues in the detoxication process in this animal.
已知多氯联苯会导致哺乳动物细胞色素P450依赖性单加氧酶活性诱导以及抗氧化防御改变。为确定虹鳟（Oncorhynchus mykiss）是否激活了类似的解毒过程，我们研究了在注射后6周腹腔注射5 mg/kg体重3,3',4,4'-四氯联苯的该物种中P450依赖性酶活性、抗氧化酶和谷胱甘肽状态（还原型和氧化型谷胱甘肽，GSH和GSSG）。乙氧异吩唑酮O-脱乙基酶活性在肝脏和肾脏中分别增加了11倍和40倍。这些器官中的UDP葡萄糖醛酸基转移酶活性分别高出2倍和5倍，而与对照组相比，注射四氯联苯的虹鳟肝脏中谷胱甘肽S-转移酶活性增强超过2倍。给药鱼的肝脏和白色肌肉中谷胱甘肽过氧化物酶活性增加。暴露于四氯联苯导致谷胱甘肽还原酶活性显著增加，肝脏中增加7倍，肾脏、红色和白色肌肉中活性显著升高。同样，注射虹鳟白色肌肉中的胞质超氧化物歧化酶和过氧化氢酶活性增加。暴露于四氯联苯显著增加了肝脏和肾脏中的GSH浓度，而肝脏和血浆中的GSSG水平增加。然而，这些变化并未改变这些组织中的GSSG/GSH比率。总体而言，这些结果表明四氯联苯对虹鳟组织中的GSH状态和抗氧化酶有重大影响，并确定白色肌肉以及肝脏和肾脏是该动物解毒过程中的重要组织。
