Hepatic uptake and disposition of human polymeric IgA1 in perfused rat liver: evidence for incomplete biliary excretion and intrahepatic degradation.
Hepatic uptake and disposition of human polymeric IgA1 in perfused rat liver: evidence for incomplete biliary excretion and intrahepatic degradation.
复制标题
灌注大鼠肝脏中人聚合 IgA1 的肝脏摄取和处置：不完全胆汁排泄和肝内降解的证据。
DOI：
10.1152/ajpgi.1985.248.4.g450
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发表时间：
1985
期刊：
影响因子：
--
通讯作者：
Brown,WR
中科院分区：
文献类型：
--
作者：
Finck,MH;Reichen,J;Vierling,JM;Kloppel,TM;Brown,WR
多聚免疫球蛋白A（伊加）的肝摄取由分泌组分介导;所得分泌型伊加完整地排泄到胆汁中。要定义的肝脏代谢的多聚伊加，我们定量的摄取和运输的人多聚IgA 1后，一个单一的通过灌注大鼠肝脏。多聚IgA 1的摄取进行了比较，与asialoorosomucoid，糖蛋白的摄取介导的asialoglycoprotein受体。125 I-聚合IgA 1和125 I-脱唾液酸类粘蛋白的单次肝脏摄取平均值分别为18.0 +/- 3.1%（SE）和71.8 +/-2.8%。125 I-多聚IgA 1的摄取被过量的未标记的多聚IgA 1抑制，但不被无唾液酸类粘蛋白抑制。只有13.0 +/- 1.6%的125 I-聚合的IgA 1提取的肝脏被排泄到胆汁中，而四分之三被释放到肝静脉流出物中的降解形式。因此，无论是摄取和胆汁排泄的聚合IgA 1的大鼠肝脏是低效的过程。聚合的IgA 1在被肝脏摄取后遵循两种不同的途径：一小部分完整地排泄到胆汁中，而大部分被降解并释放回循环中。
The hepatic uptake of polymeric immunoglobulin A (IgA) is mediated by secretory component; the resulting secretory IgA is excreted intact into bile. To define the hepatic metabolism of polymeric IgA, we quantitated the uptake and transport of human polymeric IgA1 after a single pass through the perfused rat liver. Uptake of polymeric IgA1 was compared with that of asialoorosomucoid, a glycoprotein whose uptake is mediated by the asialoglycoprotein receptor. Single-pass hepatic uptake of 125I-polymeric IgA1 and of 125I-asialoorosomucoid averaged 18.0 +/- 3.1% (SE) and 71.8 +/- 2.8%, respectively. The uptake of 125I-polymeric IgA1 was inhibited by excess unlabeled polymeric IgA1 but not by asialoorosomucoid. Only 13.0 +/- 1.6% of the 125I-polymeric IgA1 extracted by the liver was excreted into bile, whereas three-fourths was released into the hepatic venous effluent in degraded form. Thus, both the uptake and biliary excretion of polymeric IgA1 by the rat liver are inefficient processes. Polymeric IgA1 follows two distinct pathways after uptake by the liver: a small proportion is excreted intact into bile, while the majority is degraded and released back into the circulation.