title: Effects of chronic and acute lead treatments on the biophysical properties of erythrocyte membranes, and a comparison with model membranes.
abstract: Rat erythrocytes, or erythrocyte membrane ghosts, have been subjected to either chronic (drinking water containing 15 mM lead acetate for 3 months) or acute (10(-9)-10(-2 )M lead acetate for 1 h) Pb(2+) treatments and subsequent changes in membrane properties have been measured. Pb(2+) concentration in chronically treated rat plasma was 1.8 μM, which is one order of magnitude above normal values. Membrane permeability, or hemolysis, was increased in both cases. A comparative study using liposomes, in the form of large unilamellar vesicles, also indicated an increase in membrane permeability. Membrane microviscosity, or acyl chain molecular order, measured as DPH fluorescence polarization, showed an increased order in the acute treatments, at least below 700 μM Pb(2+), and a similar increase in chronically treated rats. The correlation between acute and chronic treatments, and between cell and model membranes, suggests that the present observations may be relevant in the pathogenesis of lead intoxication in humans.
authors.affiliation: Unidad de Biofísica (CSIC-UPV/EHU), and Departamento de Bioquímica, Universidad del País Vasco, Bilbao, Spain ; Institut de Formation aux Carrières de Santé de Rabat (IFCSR). Avenue Hassan II, Kilomètre 4,5 Rabat, 10000 Maroc.
authors.forename: Hasna
authors.initials: H
authors.lastname: Ahyayauch
authors.forename: Wafae
authors.initials: W
authors.lastname: Sansar
authors.forename: Adela
authors.initials: A
authors.lastname: Rendón-Ramírez
authors.forename: Félix M
authors.initials: FM
authors.lastname: Goñi
authors.forename: Mohammed
authors.initials: M
authors.lastname: Bennouna
authors.forename: Halima
authors.initials: H
authors.lastname: Gamrani
keywords: Lead; erythrocyte membrane; liposomes; membrane lipid order; membrane permeability