title: Topography and dynamics of receptors for acetylated and malondialdehyde-modified low-density lipoprotein in the plasma membrane of mouse peritoneal macrophages as visualized by colloidal gold in conjunction with surface replicas.
abstract: The topography and dynamics of receptors for acetylated (acetyl) and malondialdehyde-modified (MDA) low-density lipoprotein (LDL) in the plasma membrane of cultured mouse peritoneal macrophages were investigated using a new technique. Modified LDL labeled with gold particles was used to visualize LDL receptors in the plane of the plasma membrane in platinum-carbon surface replicas of critical point-dried cells. It was found that the native distribution of unoccupied acetyl-LDL receptors is diffuse, whereas unoccupied MDA-LDL receptors are preclustered in the plasma membrane. Competition and double labeling experiments suggest the existence of two distinct classes of receptor sites for acetyl-LDL and MDA-LDL.
mesh_terms: D000107:Acetylation; D000818:Animals; D002462:Cell Membrane / Q000648:ultrastructure; D002478:Cells, Cultured; D003102:Colloids; D006046:Gold; D006801:Humans; D007202:Indicators and Reagents; D008077:Lipoproteins, LDL / Q000032:analysis*; D008264:Macrophages / Q000648:ultrastructure*; D008297:Male; D008314:Malonates / Q000494:pharmacology*; D008315:Malondialdehyde / Q000494:pharmacology*; D051379:Mice; D008815:Mice, Inbred Strains; D008854:Microscopy, Electron; D011973:Receptors, LDL / Q000032:analysis*
chemical_list: D003102:Colloids; D007202:Indicators and Reagents; D008077:Lipoproteins, LDL; D008314:Malonates; D011973:Receptors, LDL; D008315:Malondialdehyde; D006046:Gold