Pharmacokinetics of methylmercury in sheep.
Pharmacokinetics of methylmercury in sheep.
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甲基汞在羊体内的药代动力学。
DOI：
10.1002/jat.2550030108
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发表时间：
1983
期刊：
影响因子：
--
通讯作者：
Kostyniak,PJ
中科院分区：
文献类型：
--
作者：
Kostyniak,PJ
对绵羊单次静脉注射203汞标记甲基汞后的药代动力学进行了初步研究。定期采血，测定血浆和全血203汞。血液和血浆中的203汞浓度呈双相指数下降。血浆203汞的半衰期为14.6天，全血半衰期为14.1天。在整个研究过程中，203汞在红细胞和血浆中的分布是均匀的。获得了14.9：1的红细胞与血浆浓度比，血液中约88%的203汞与红细胞部分有关。粪便和羊毛都是主要的排泄途径。在第8天采集的羊毛中，大约有18%的剂量存在于羊毛中。相比之下，在同一时间段，粪便中的总排泄量为剂量的11.5%。与全血曲线末端成分减少32.5%相比，29.5%的总数是有利的。从根部对羊毛的顺序分析显示，203汞的浓度增加到了一个峰值。用羊毛中首次出现的203汞标签作为确定羊毛生长速度的标志，羊毛中的203汞呈现指数下降，减半时间类似于全血和血浆。羊毛与血液的比例估计约为120：1。牺牲时的组织分析显示，203汞标记在大脑中分布相当均匀。在脊髓和神经节中观察到的水平略低。肾脏的汞浓度最高，可食用肌肉的浓度大约是血液浓度的6倍。胆汁中的203汞浓度是血浆中的三倍，这与观察到的大量粪便排泄一致。绵羊可能是研究甲基汞在中枢神经系统的区域性沉积和甲基汞沉积到毛发中的机制的有用动物模型。
A preliminary study of the pharmacokinetics of methylmercury was performed in sheep after a single intravenous dose of203Hg‐labeled methylmercury. Blood samples were taken periodically, and plasma and whole blood203Hg were determined. Blood and plasma203Hg concentrations exhibited a biphasic exponential decline. The half‐time for the major component was 14.6 days for plasma203Hg and 14.1 days for whole blood. There was a uniform distribution of203Hg between red cells and plasma throughout the study. A red cell to plasma concentration ratio of 14.9:1 was obtained, with approximately 88% of the203Hg in blood associated with the red cell fraction. Both the feces and the wool represented major routes of excretion. Approximately 18% of the dose was present in the wool taken on day 8. This is compared with a total excretion in the feces of 11.5% of the dose over the same time course. The total of 29.5% compares favorably with a reduction of 32.5% in the terminal component of the whole blood curve. Sequential analysis of wool from the root end revealed increasing concentrations of203Hg to a peak. Using the first appearance of the203Hg label in the wool as a marker to determine the wool growth rate, the203Hg in wool shewed an exponential decline with a half‐time similar to that seen for whole blood and plasma. The wool to blood ratio was estimated to be approximately 120:1. Tissue analysis at sacrifice revealed a rather uniform distribution of203Hg label in the brain. Somewhat lower levels were observed in the spinal cord and ganglia. Kidney had the highest203Hg concentration, and edible muscle had approximately six times the concentration measured in blood. The concentration of203Hg was three times higher in bile than in plasma, consistent with the substantial fecal excretion observed. The sheep may be a useful animal model for studying regional deposition of methylmercury in the CNS and mechanisms of methylmercury deposition into hair.