title: Effects of lead chloride on human erythrocyte membranes and on kinetic anion sulphate and glutathione concentrations.
abstract: Our study concerns the effects of exposure to lead chloride on the morphology, K(+) efflux, SO(4)(-) influx and GSH levels of the human erythrocyte. Blood was collected in heparinized tubes and washed three times. The cells were suspended at 3% hematocrit and incubated for 1 h at 25°C in a medium containing increasing concentrations of lead chloride (0, 0.3, 0.5 and 1 μM). After incubation, the suspensions were centrifuged and the erythrocyte pellets were divided into three aliquots for testing. The results show: an increase in the permeability of erythrocytes treated with lead chloride with consequent damage and cellular death, especially in the presence of high concentrations; an increase in potassium ion efflux; alterations in the morphology and membrane structure of the red blood cells; and a decrease in sulphate uptake, due either to the oxidative effect of this compound on the band 3 protein, which loses its biological valence as a carrier of sulphate ions, or to a decrease in the ATP erythrocyte concentration. In conclusion, the exposure of erythrocytes to Pb(2+) ions leads to a reduction in the average lifetime of the erythrocytes and the subsequent development of anemia. These data are discussed in terms of the possible effect of lead on the reduction-oxidation systems of the cell. Oxidant agents, such as lead, are known to cross-link integral membrane proteins, leading to K/Cl-cotransport. The increased K(+) efflux affects the altered redox state.
authors.affiliation: Dipartimento di Scienze della Vita M. Malpighi, Facoltà di Scienze MMFFNN, Università degli Studi di Messina, Messina, Italy. tiziana_gugliot@yahoo.it
authors.forename: Tiziana
authors.initials: T
authors.lastname: Gugliotta
authors.forename: Grazia
authors.initials: G
authors.lastname: De Luca
authors.forename: Pietro
authors.initials: P
authors.lastname: Romano
authors.forename: Caterina
authors.initials: C
authors.lastname: Rigano
authors.forename: Adriana
authors.initials: A
authors.lastname: Scuteri
authors.forename: Leonardo
authors.initials: L
authors.lastname: Romano
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D001457:Anion Exchange Protein 1, Erythrocyte / Q000378:metabolism; D000838:Anions / Q000737:chemistry; D017209:Apoptosis / Q000187:drug effects; D002463:Cell Membrane Permeability / Q000187:drug effects; D004910:Erythrocyte Membrane / Q000187:drug effects* / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism*; D006801:Humans; D007700:Kinetics; D007854:Lead / Q000633:toxicity*; D010084:Oxidation-Reduction; D011188:Potassium / Q000378:metabolism; D013431:Sulfates / Q000378:metabolism*
chemical_list: D001457:Anion Exchange Protein 1, Erythrocyte; D000838:Anions; D013431:Sulfates; D007854:Lead; C029891:lead chloride; D000255:Adenosine Triphosphate; D005978:Glutathione; D011188:Potassium