Binding of apoA-IV-phospholipid complexes to plasma membranes of rat liver |
| |
| Authors: | G Ghiselli W L Crump A M Gotto |
| |
| Institution: | 2. Division of Hematology, Department of Medicine, Stanford Cancer Institute, Stanford University, Stanford, California, USA;3. Department of Bioengineering, Stanford University, Stanford, California, USA;4. Molecular Imaging Program at Stanford, The James H Clark Center, Stanford University, Stanford, California, USA;5. Department of Radiology, Stanford University School of Medicine, Stanford, California, USA |
| |
| Abstract: | Rat apoA-IV complexes with dimyristoyl phosphatidylcholine (apoA-IV-DMPC) have been prepared and their ability to bind to purified rat liver plasma membranes investigated. Binding equilibrium at 37 degrees C was reached in 30 minutes. Saturation binding experiments and subsequent analysis of the results with Scatchard plots gave results consistent with the presence of a single saturable binding site. DMPC or POPC unilamellar vesicles could not compete with apoA-IV-DMPC for binding; apoA-I-DMPC competed only partially. ApoE-poor HDL effectively competed with apoA-IV-DMPC. The fact that binding could be greatly reduced (greater than 70%) by preincubating the membrane with pronase (18 micrograms/ml), supports the conclusion that a membrane protein is involved in binding. Based on these results, we speculate that the rapid catabolism of apoA-IV in plasma may be mediated by a specific uptake mechanism in the liver. The implications of these results support the hypothesis that apoA-IV is involved in reverse cholesterol transport. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
