Affiliations: Institute of Biochemistry, Faculty of Medicine of Lisbon, Lisbon 1649‐028, Portugal
Note: [] Corresponding author: Rui Mesquita, Instituto de Bioquímica, Faculdade de Medicina de Lisboa, Av. Prof. Egas Moniz, 1649‐028 Lisboa, Portugal, Tel.: +351 21 7985136; Fax: + 351 21 7939791; E‐mail: [email protected].
Abstract: NO is present in the blood at 10−7 M under physiological conditions, but at concentrations higher than 10−6 M during inflammatory disease states. The aim of this study was to characterize what are the effects of these different NO concentrations on erythrocyte structural and functional properties. Blood was collected from eleven healthy men and incubated with SpermineNONOate in order to expose it during incubation time to NO concentrations between 10−7 M and 10−3 M. We measured erythrocyte aggregation and deformability, membrane lipid peroxidation and fluidity, p50, hemoglobin, oxyhemoglobin, methemoglobin concentrations and plasma pH, pO2, pCO2, Na+, K+ and Ca2+. When blood was exposed to NO 10−7 M erythrocyte deformability increase and p50 decrease. In presence of NO 10−5 M lipid fluidity and p50 decrease. When blood was exposed to NO 10−3 M methemoglobin concentration increase and erythrocyte deformability and p50 decrease but membrane fluidity and lipid peroxidation were similar to control. In conclusion, dependent of NO concentrations there is different effects on erythrocytes structural and functional properties.
