代谢
汞主要通过摄入和吸入被吸收,然后通过血液流布全身,其中一部分会与血红蛋白上的巯基团结合。由于汞蒸汽具有脂溶性,吸入暴露后容易进入红细胞和中枢神经系统。一旦进入细胞内,汞蒸汽可以通过过氧化氢酶-过氧化氢途径发生氧化,变成汞离子。汞原子能够扩散到过氧化氢酶酶裂中,到达含有血红素环的活性位点。由于过氧化氢酶-过氧化氢途径普遍存在,氧化很可能发生在所有组织中。氧化后,汞倾向于在肾脏中积累。有机汞和元素汞也可以穿过胎盘和血脑屏障,因此也会在大脑中积累。汞主要通过呼出和粪便排出体外。
Mercury is absorbed mainly via ingestion and inhalation, then distributed throughout the body via the bloodstream, where a portion binds to sulfhydryl groups on haemoglobin. Being lipid soluble, mercury vapor readily enters the red blood cells and the central nervous system following inhalation exposure. Once inside the cell, mercury vapor can undergo oxidation to mercuric mercury, which takes place via the catalase–hydrogen peroxide pathway. The mercury atom is able to diffuse down the cleft in the catalase enzyme to reach the active site where the heme ring is located. Oxidation most likely occurs in all tissue, as the catalase hydrogen peroxide pathway is ubiquitous. Following oxidation, mercury tends to accumulate in the kidneys. Organic and elemental mercury can also penetrate the placenta and blood-brain barrier, and thus also accumulate in the brain. Mercury is excreted mainly by exhalation and in the faeces. (A6, L7)
来源:Toxin and Toxin Target Database (T3DB)