Response of human blood platelet membrane to sodium selenite.
It was demonstrated that incubation of blood platelets with sodium selenite (1-100 microM) resulted in a dose- and time-dependent loss of platelet thiols (both glutathione and protein -SH groups). The effects of sodium selenite on platelet membrane lipid fluidity by the EPR spin-labelling method was also investigated. We showed there were no alterations in membrane fluidity at the deeper regions (12-DOXYL-Ste) in lipid bilayer, a slight increase (approx. 7%, p < 0.03) of h +1/h0 for spin probe 5-DOXYL-Ste was monitored. The amount of Triton-insoluble protein fraction isolated from platelets after incubation (60 min) with selenite was significantly elevated (p < 0.006). It has been suggested that limited increase in lipid fluidity at the surface regions in the lipid bilayer of the platelet membrane in selenite-treated platelets may be the result of alteration in lipid-protein interactions caused by protein conformational changes.
Zbikowska
H M
HM
Department of General Biochemistry, Univeristy of Lódź, Poland. zbikow@biol.uni.lodz.pl
Gwoździński
K
K
Wachowicz
W
W
Krajewski
T
T
D000818:Animals; D001792:Blood Platelets / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology / Q000648:ultrastructure; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D002478:Cells, Cultured; D003902:Detergents; D004305:Dose-Response Relationship, Drug; D004578:Electron Spin Resonance Spectroscopy; D006801:Humans; D007700:Kinetics; D008051:Lipid Bilayers / Q000097:blood; D017830:Octoxynol; D018038:Sodium Selenite / Q000494:pharmacology*; D013113:Spin Labels; D013552:Swine
D003902:Detergents; D008051:Lipid Bilayers; D013113:Spin Labels; D017830:Octoxynol; D018038:Sodium Selenite