Delayed alteration of membrane fluidity in intact cultured B-16 melanoma cells affected by ultraviolet irradiation.
Lipid peroxidation in the plasma membrane has been reported to decrease membrane fluidity. We examined membrane fluidity in relation to lipid peroxidation processes after UV-B exposure of cultured B-16 melanoma cells. UV exposure promptly increased TBA-positive material(s), but alteration of membrane fluidity was delayed. Plasma membrane fluidity increased significantly 6 hours after exposure when the TBA-value(s) had become under the control level. To examine the direct effect of lipid peroxides on the fluidity, tert-butyl hydroperoxide was added to B-16 melanoma cells. Similar results were obtained with respect to membrane fluidity. These results suggest that lipid peroxidation at UV doses maintaining cell viability does not directly induce a significant alteration of membrane fluidity, but may influence the fluidity either during metabolizing processes of UV-induced lipid peroxides or during repair processes following oxidative cell membrane damage.
D000818:Animals; D002460:Cell Line; D002470:Cell Survival / Q000528:radiation effects; D003497:Cyclic N-Oxides; D004578:Electron Spin Resonance Spectroscopy; D007700:Kinetics; D008545:Melanoma / Q000378:metabolism*; D008560:Membrane Fluidity / Q000187:drug effects*; D051379:Mice; D010545:Peroxides / Q000494:pharmacology; D013113:Spin Labels; D014466:Ultraviolet Rays; D020122:tert-Butylhydroperoxide
D003497:Cyclic N-Oxides; D010545:Peroxides; D013113:Spin Labels; C037404:12-doxylstearic acid; D020122:tert-Butylhydroperoxide