Vesicle release from rat red cell ghosts and increased association of cell membrane proteins with cytoskeletons induced by cadmium.
When rat red cell ghosts were incubated with 0.1-0.5 mM CdCl2 in 10 mM Tris-HCl (pH 7.4) at 37 degrees C for 30 min, they became irregular in shape and released small vesicles. The release of vesicles was dependent on the incubation temperature and Cd2+ concentration. The maximum release occurred at 37 degrees C in the presence of 0.2 mM Cd2+. The protein composition of Cd2+-induced vesicles was similar to that of the vesicles released from ATP-depleted red cells. Upon incubation with 0.1-0.2 mM Cd2+, more than 90% of the Cd2+ added to the incubation buffer was recovered in ghosts and 15-20% of the ghost Cd2+ was located on the cytoskeletons prepared by washing ghosts with 0.5% Triton X-100 solution containing 0.1 M KCl and 10 mM Tris-HCl (pH 7.4). Moreover, the cytoskeletons prepared from Cd2+-treated ghosts markedly contained cell membrane proteins, bands 2.1, 3, 4.2 and 4.5, and glycophorins. The association of bands 3 and 4.2 with cytoskeletons increased with increasing concentrations of Cd2+ added to the incubation buffer and saturated at 0.2 mM Cd2+. The solubilization of cytoskeletal proteins, bands 1, 2 and 5, from ghosts at low ionic strength was almost completely suppressed by preincubation of ghosts with 0.1 mM Cd2+. HgCl2, PbCl2 and ZnCl2 at 0.2 mM each also produced an increased association of cell membrane proteins with cytoskeletons, whereas CaCl2 and MgCl2 did not.
D000199:Actins / Q000097:blood; D000818:Animals; D002021:Buffers; D002104:Cadmium / Q000097:blood / Q000494:pharmacology*; D002413:Cations, Divalent / Q000494:pharmacology; D003599:Cytoskeleton / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D004910:Erythrocyte Membrane / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D066298:In Vitro Techniques; D008297:Male; D008565:Membrane Proteins / Q000097:blood*; D009994:Osmolar Concentration; D011485:Protein Binding / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains; D012995:Solubility; D013049:Spectrin / Q000378:metabolism; D013439:Sulfhydryl Reagents / Q000494:pharmacology
D000199:Actins; D002021:Buffers; D002413:Cations, Divalent; D008565:Membrane Proteins; D013439:Sulfhydryl Reagents; D002104:Cadmium; D013049:Spectrin