Patterns of filipin-sterol complex distribution in intact erythrocytes and intramembrane particle-aggregated ghost membranes.
When fixed erythrocytes are exposed to the cholesterol probe, filipin, and freeze-fractured, their membrane is labeled with only a limited number of typical, 25 nm diameter filipin-sterol complexes. In addition, the membrane contains many less distinct filipin-induced perturbations that give it an overall rippled appearance. In contrast, red cell ghosts subjected to conditions that result in an aggregation of their intramembrane particles have large particle-free membrane domains which are completely filled with 25 nm filipin-sterol complexes. These results suggest that some constraint exists in the intact erythrocyte membrane which restricts the formation of typical filipin-sterol complexes.
D000818:Animals; D002784:Cholesterol / Q000097:blood*; D004910:Erythrocyte Membrane / Q000648:ultrastructure*; D004912:Erythrocytes / Q000648:ultrastructure*; D005372:Filipin; D005614:Freeze Fracturing; D008563:Membrane Lipids / Q000097:blood; D008854:Microscopy, Electron; D011090:Polyenes; D051381:Rats
D008563:Membrane Lipids; D011090:Polyenes; D005372:Filipin; D002784:Cholesterol