title: In vitro effects of oxygen on physico-chemical properties of horse erythrocyte membrane.
abstract: Whether direct exposure to different concentrations (0%, 13%, 100%) of oxygen may affect horse erythrocyte membrane fluidity (EMF) and fatty acid (FA) composition was studied during 1 (T60) and 2h (T120) exposure. EMF was investigated at the head group level and hydrophobic core thanks to phosphorus nucleus 31 ((31)P) nuclear magnetic resonance ((31)P NMR) and electronic paramagnetic resonance (EPR) using two spin probes: 5-nitroxydestearic acid and 16-doxylstearic acid. Lipid structure of the membranes was studied by gas liquid chromatography. 4-Hydroxy-2E-nonenal was also analyzed as a marker of lipid peroxidation. It increased at T120 13% and 100% oxygen whereas there were no significant changes in membrane dynamic or structure. Correlation was demonstrated between EMF and partial pressure of oxygen in the blood ( [Formula: see text] ). In vitro high rate of oxygenation was efficient to induce lipid peroxidation but did not change membrane dynamics. This may be due to a low free radical production in vitro or to the high red blood cells antioxidant properties.
authors.affiliation: Equine Department, National Veterinary School of Lyon, Lyon, France.
authors.forename: Karine
authors.initials: K
authors.lastname: Portier
authors.forename: Michel
authors.initials: M
authors.lastname: Guichardant
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Debouzy
authors.forename: David
authors.initials: D
authors.lastname: Crouzier
authors.forename: Ingrid
authors.initials: I
authors.lastname: Geraud
authors.forename: Nathalie
authors.initials: N
authors.lastname: Kirschvink
authors.forename: Pierre
authors.initials: P
authors.lastname: Lekeux
authors.forename: Nicole
authors.initials: N
authors.lastname: Fellmann
authors.forename: Jean
authors.initials: J
authors.lastname: Coudert