Fisheries College of Huazhong Agricultural University, Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Wuhan 430070, People's Republic of China.
Environ Toxicol Pharmacol. 2009 Mar;27(2):195-9. doi: 10.1016/j.etap.2008.10.005. Epub 2008 Oct 28.
Oxidative stress response after prolonged exposure to a low dose of microcystins (MCs) was studied in liver, kidney and brain of domestic rabbits. Rabbits were treated with extracted MCs (mainly MC-LR and MC-RR) at a dose of 2 MC-LReq. μg/kg body weight or saline solution every 24h for 7 or 14 days. During the exposure of MCs, increase of lipid peroxidation (LPO) levels were detected in all the organs studied, while antioxidant enzymes responded differently among different organs. The enzyme activities of superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GR) in liver decreased in the MCs treated animals. In brain, there were obvious changes in glutathione peroxidase (GPx) and GR, while only CAT was obviously influenced in kidney. Therefore, daily exposure at a lower dosage of MCs, which mimicked a natural route of MCs, could also induce obvious oxidative stress in diverse organs of domestic rabbits. The oxidative stress induced by MCs in brain was as serious as in liver and kidney, suggesting that brain may also be a target of MCs in mammals. And it seems that animals may have more time to metabolize the toxins or to form an adaptive response to reduce the adverse effects when exposed to the low dose of MCs.
研究了家兔在长期低剂量微囊藻毒素（MCs）暴露后肝、肾和脑的氧化应激反应。兔子以每 24 小时 2 MC-LReq. μg/kg 体重的剂量或生理盐水每 24 小时处理一次，连续 7 或 14 天。在 MCs 暴露期间，在所有研究的器官中均检测到脂质过氧化（LPO）水平升高，而抗氧化酶在不同器官中的反应不同。MCs 处理动物的肝中超氧化物歧化酶（SOD）、过氧化氢酶（CAT）和谷胱甘肽还原酶（GR）的酶活性降低。在脑中有明显的谷胱甘肽过氧化物酶（GPx）和 GR 变化，而在肾中只有 CAT 明显受影响。因此，每天以较低剂量暴露于 MCs，模拟 MCs 的自然途径，也可在家兔的不同器官中引起明显的氧化应激。MCs 在脑中引起的氧化应激与在肝和肾中一样严重，表明脑可能也是哺乳动物中 MCs 的靶器官。而且，当暴露于低剂量的 MCs 时，动物似乎有更多的时间来代谢毒素或形成适应性反应以减少不良反应。
