Mathews H B, Anderson M W
Drug Metab Dispos. 1975 Sep-Oct;3(5):371-80.
The distribution and excretion of four 14C-labeled polychlorinated biphenyls (PCB), 4-chloro-, 4,4'-dichloro-, 2,4,5,2',5'-pentachloro-, and 2,4,5,2',4',5'-hexachlorobiphenyl, were studied in the rat. Total radioactivity was determined in the major organs and tissues at times varying from 15 min up to 42 days after an intravenous injection of a single 0.6-mg dose of each of the PCB's per kg. Each of the PCB's was removed rapidly from the blood and initially stored largely in the liver and muscle. The rates of the subsequent redistribution of the PCB's and their metabolites to the adipose tissue and skin and/or excretion could be related to the degree of chlorination. The relative amounts of each PCB and its metabolites in each major tissue were determined at selected time points. The percentage of the total radioactivity accounted for by metabolites of the PCB's decreased as the chlorination of the PCB's increased, but storage of metabolites did not account for a significant portion of any of the PCB doses. Excretion accounted for more than 90% of the dose of the mono-, di-, and pentachlorobiphenyls during the time period studies, whereas extrapolation of the hexachlorobiphenyl data indicated that less than 20% of the dose would ever be excreted. The rates of elimination of the PCB's were apparently determined primarily by their rates of metabolism. The effect of degree and position of chlorination on the rate of metabolism of the biphenyl molecule is discussed.
在大鼠体内研究了四种14C标记的多氯联苯（PCB），即4-氯联苯、4,4'-二氯联苯、2,4,5,2',5'-五氯联苯和2,4,5,2',4',5'-六氯联苯的分布与排泄情况。静脉注射每千克0.6毫克的上述每种PCB单剂量后，在15分钟至42天的不同时间点测定主要器官和组织中的总放射性。每种PCB都能迅速从血液中清除，最初主要储存在肝脏和肌肉中。随后PCB及其代谢产物向脂肪组织和皮肤的再分布速率以及排泄速率可能与氯化程度有关。在选定的时间点测定每种主要组织中每种PCB及其代谢产物的相对含量。随着PCB氯化程度的增加，PCB代谢产物占总放射性的百分比下降，但代谢产物的储存量在任何一种PCB剂量中都不占很大比例。在研究期间，一氯、二氯和五氯联苯剂量的90%以上通过排泄排出，而六氯联苯数据的外推表明，该剂量中只有不到20%会被排泄。PCB的消除速率显然主要由其代谢速率决定。文中讨论了氯化程度和位置对联苯分子代谢速率的影响。
