期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1978
卷号:75
期号:7
页码:3459-3463
DOI:10.1073/pnas.75.7.3459
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:The major abnormal plasma lipoprotein of cholestasis (LP-X) was isolated from blood plasma and from perfusates of isolated livers of rats with biliary obstruction. In both cases LP-X was composed mainly of about equimolar parts of phospholipids and unesterified cholesterol; the small protein component was primarily the arginine-rich apolipoprotein. By electron microscopy, LP-X appeared as a unilamellar liposome (690 A mean diameter, range 400-1000 A) with the trilaminar staining image typical of phospholipid bilayers. Extensive block staining of cholestatic livers for 48 hr with warmed uranyl acetate (37 degrees) permitted the visualization of vesicles indistinguishable from LP-X within hepatic parenchyma. These trilaminar-staining vesicles occurred predominantly within bile canaliculi. They also were seen in nearby cytoplasmic vacuoles or invaginations between hepatocytes and in the space of Disse. Similar vesicles were not seen in the endoplasmic reticulum or Golgi cisternae. These observations raise the possibility that the vesicles are formed within bile canaliculi and are transported from the canaliculi to the space of Disse within pinocytotic vacuoles.