J Toxicol Sci. 2011 Jan;36(1):121-6. doi: 10.2131/jts.36.121.
To investigate the influence of Chlorella (Parachlorella beijerinckii) on the excretion and tissue accumulation of methylmercury (MeHg), we orally administered 5 mg/kg of MeHg chloride (4 mg Hg/kg) to female C57BL/6N mice (aged 10 weeks). The mice were housed in metabolism cages to collect urine and feces for 3 weeks with diets containing 0%, 5%, or 10% P. beijerinckii powder (BP) in a basal diet (CE-2). The lowered blood Hg levels in the 5% and 10% BP groups became significant compared to those of the control group (0% BP) as early as day 7. During the 21 days of testing, significant increases in the cumulative Hg eliminations into urine (5% BP) and feces (5% and 10% BP) were found in the BP groups. Twenty-one days after administration, the organ Hg levels in both BP groups tended to decrease compared to that of the control group. The reduction of Hg levels in the kidney and brain were significant, whereas that in the liver was not. Although tissue Hg levels are known to be closely related to glutathione (GSH) metabolism, no difference was found in GSH levels in the blood or organs between the control group and the 10% BP group. These results suggest that continuous BP intake accelerates the excretion of MeHg and subsequently decreases tissue Hg levels in mice, with no alteration of GSH metabolism. We should conduct further research to elucidate details regarding the mechanism of BP-induced enhancement of MeHg excretion.
为了研究小球藻（巴夫藻）对甲基汞（MeHg）排泄和组织积累的影响，我们给 10 周龄的雌性 C57BL/6N 小鼠经口灌胃 5mg/kg 的 MeHg 氯化物（4mgHg/kg）。将小鼠饲养在代谢笼中，用含有基础饮食（CE-2）中 0%、5%或 10%巴夫藻粉（BP）的饮食收集 3 周的尿液和粪便。与对照组（0%BP）相比，5%和 10%BP 组的血液 Hg 水平早在第 7 天就显著降低。在 21 天的测试期间，BP 组尿液（5%BP）和粪便（5%和 10%BP）中的累积 Hg 排泄量显著增加。给药 21 天后，与对照组相比，BP 组各器官的 Hg 水平趋于降低。肾脏和大脑中的 Hg 减少量显著，而肝脏中的 Hg 减少量不显著。尽管组织 Hg 水平与谷胱甘肽（GSH）代谢密切相关，但对照组和 10%BP 组之间的血液或器官中的 GSH 水平没有差异。这些结果表明，连续摄入 BP 可加速 MeHg 的排泄，从而降低小鼠组织中的 Hg 水平，而 GSH 代谢没有改变。我们应该进行进一步的研究，阐明 BP 诱导 MeHg 排泄增强的机制的细节。
