Solubility of gases in human red blood cell ghosts

Power, G. G.; Stegall, H F

doi:10.1152/jappl.1970.29.2.145

Cited by 62 publications

(25 citation statements)

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“…The corrosion of the alloy disks starts immediately after implantation and the initial evolution of H 2 drives the formation of the cavity, pushing surrounding tissues layers apart. Simultaneously, H 2 is expected to saturate the adjacent tissues although the solubility of H 2 in cells and aqueous media such as biological fluids is low [35,36]. While the alloy disks continue to corrode and the size of the cavities increases, the evolving H 2 in the growing cavities continuously exchanges with dissolved gases like N 2 , O 2 and CO 2 from the neighboring tissues and blood vessels [37].…”

Section: Resultsmentioning

confidence: 99%

Fast escape of hydrogen from gas cavities around corroding magnesium implants

et al. 2013

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Magnesium materials are of increasing interest in the development of biodegradable implants as they exhibit properties that make them promising candidates. However, the formation of gas cavities after implantation of magnesium alloys has been widely reported in the literature. The composition of the gas and the concentration of its components in these cavities are not known as only a few studies using non-specific techniques were done about 60 years ago. Currently many researchers assume that these cavities contain primarily hydrogen because it is a product of magnesium corrosion in aqueous media. In order to clearly answer this question we implanted rare earth-containing magnesium alloy disks in mice and determined the concentration of hydrogen gas for up to 10 days using an amperometric hydrogen sensor and mass spectrometric measurements. We were able to directly monitor the hydrogen concentration over a period of 10 days and show that the gas cavities contained only a low concentration of hydrogen gas, even shortly after formation of the cavities. This means that hydrogen must be exchanged very quickly after implantation. To confirm these results hydrogen gas was directly injected subcutaneously. Most of the hydrogen gas was found to exchange within 1h after injection. Overall, our results disprove the common misbelief that these cavities mainly contain hydrogen and show how quickly this gas is exchanged with the surrounding tissue.

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Section: Resultsmentioning

confidence: 99%

Fast escape of hydrogen from gas cavities around corroding magnesium implants

et al. 2013

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“…The K P of ⅐ NO between lipid and aqueous phases was determined for the first time using this equilibrium-shift method, demonstrating that ⅐ NO concentrates 4.4 -3.4-fold in membranes and LDL, respectively, and similar results were obtained with O 2 (Table I). Evidencing the difficulties in measuring K P using amphiphilic lipid phases, the K P of O 2 between membranes and water has only been measured in dimyristoyl phosphatidylcholine liposomes and erythrocyte plasma mem- branes (37,39). Smotkin et al (37), found K P ϭ 3.7 Ϯ 0.6 for O 2 between dimyristoyl phosphatidylcholine liposomes in the liquid crystalline state and water, measuring total O 2 concentration by a modified Winkler technique.…”

Section: Discussionmentioning

confidence: 99%

“…We assumed a 0.75 bilayer hydrophobic fraction, thus the corrected K P from Smotkin et al (37) would be 4.9 Ϯ 0.8, which is in agreement within experimental errors with that found by ourselves (Table I). More complex membranes, such as erythrocyte plasma membranes, dissolve O 2 in a similar fashion, with K P ϭ 5 Ϯ 4 (39).…”

Section: Discussionmentioning

confidence: 99%

Direct Measurement of Nitric Oxide and Oxygen Partitioning into Liposomes and Low Density Lipoprotein

Möller

Botti

Batthyány

et al. 2005

Journal of Biological Chemistry

133

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Nitric oxide ( ⅐ NO) has been proposed to play a relevant role in modulating oxidative reactions in lipophilic media like biomembranes and lipoproteins. Two factors that will regulate ⅐ NO reactivity in the lipid milieu are its diffusion and solubility, but there is no data concerning the actual diffusion (D) and partition coefficients (K P ) of ⅐ NO in biologically relevant hydrophobic phases. Herein, a "equilibrium-shift" method was designed to directly determine the ⅐ NO and O 2 partition coefficients in liposomes and low density lipoprotein (LDL) relative to water. It was found that ⅐ NO partitions 4.4-and 3.4-fold in liposomes and LDL, respectively, whereas O 2 behaves similarly with values of 3.9 and 2.9, respectively. In addition, actual diffusion coefficients in these hydrophobic phases were determined using fluorescence quenching and found that ⅐ NO diffuses ϳ2 times slower ). The influence of ⅐ NO and O 2 partitioning and diffusion in membranes and lipoproteins on ⅐ NO reaction with lipid radicals and auto-oxidation is discussed. Particularly, the 3-4-fold increase in O 2 and ⅐ NO concentration within biological hydrophobic phases provides quantitative support for the idea of an accelerated auto-oxidation of ⅐ NO in lipid-containing structures, turning them into sites of enhanced local production of oxidant and nitrosating species.Nitric oxide produced by the oxidation of L-arginine to Lcitrulline by ⅐ NO 1 synthases accomplishes important physiological regulatory functions related to vasodilation, neurotransmission, immune response, and regulation of cell respiration (1, 2). Despite being a free radical, ⅐ NO is a weak redox intermediate, and its reactivity is restricted to paramagnetic species, including metals, metalloproteins (3, 4), and other radical molecules (5, 6).The reactions of ⅐ NO with other radicals can be classified as oxidant or antioxidant, depending on the reactivity of the products. Nitric oxide reacts with the superoxide anion radical (O 2 . ) at diffusion-controlled rates to yield peroxynitrite, a strong oxidant that can induce lipid and protein oxidation and nitration (6, 7). Similarly, the reaction with O 2 yields nitrogen dioxide ( ⅐ NO 2 ) and dinitrogen trioxide (N 2 O 3 ), strong oxidant and nitrosating species (8, 9). Although the reaction with O 2 is complex and not completely understood (8, 9), the rate law is second-order in ⅐ NO and first-order in O 2 , with a third-order rate constant k ϭ 0.8 -1.2 ϫ 10 7 M Ϫ2 s Ϫ1 (8, 9). On the other hand, ⅐ NO has been proposed as an important antioxidant in vivo (10 -12), mainly because it reacts with organic peroxyl radicals at near diffusion-limited rates (k ϭ 1-3 ϫ 10 9 M Ϫ1 s Ϫ1 , see Refs. 5 and 13) effectively inhibiting lipid peroxidation chain reactions (7, 10 -12, 14 -17). This antioxidant activity may be specially relevant in low density lipoprotein (LDL), because oxidatively modified lipoproteins can be recognized by scavenger receptors on macrophages and lead to macrophage lipid loading and eventually to atherosclerosis...

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“…The partition coefficient for CO 2 in the erythrocyte membrane at 37°C is around 1.6 (57). The concentration of CO 2 in the membrane provides greater availability of CO 2 for the membrane-associated CAII and consequently bicarbonate for band 3.…”

Section: Band 3 and Caii Form A Complex In The Erythrocyte-caiimentioning

confidence: 98%

Carbonic Anhydrase II Binds to the Carboxyl Terminus of Human Band 3, the Erythrocyte Cl−/HCO3−Exchanger

Vince

Reithmeier

1998

Journal of Biological Chemistry

233

227

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In this study, we provide evidence that the 33-residue carboxyl-terminal (Ct) region of the human erythrocyte chloride/bicarbonate exchanger, band 3, binds carbonic anhydrase II (CAII). Immunofluorescence showed that tomato lectin-mediated clustering of band 3 in ghost membranes caused a similar clustering of CAII, indicating an in situ association. CAII cosolubilized and coimmunoprecipitated with band 3, suggesting that the two proteins form a complex. Band 3 (K 1/2 ‫؍‬ 70 nM) or the membrane domain of band 3 (K 1/2 ‫؍‬ 100 nM) bound saturably to immobilized CAII in a solid phase binding assay. The interaction with CAII was specifically blocked by an antibody to the Ct of band 3. Affinity blotting showed that a glutathione S-transferase (GST)-fusion protein (GST-Ct) containing the last 33 residues of human band 3 bound to CAII. The solid phase binding assay showed that binding of GST-Ct to immobilized CAII was saturable (K 1/2 ‫؍‬ 20 nM). The binding rate was slow (t 1/2 ‫؍‬ 12 h) at physiological ionic strength and pH but was enhanced at low ionic strength or acidic pH. Intact band 3 (K i ‫؍‬ 15 nM), the membrane domain of band 3 (K i ‫؍‬ 100 nM), or antibodies to the Ct of band 3 were able to block GST-Ct binding to CAII, confirming the specificity of the interaction. Affinity chromatography showed that CAII bound to immobilized GST-Ct with a 1:1 stoichiometry. This work indicates that CAII, the bicarbonate supplier, is directly coupled to band 3, the chloride/bicarbonate exchanger in red blood cells.

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Solubility of gases in human red blood cell ghosts

Cited by 62 publications

References 0 publications

Fast escape of hydrogen from gas cavities around corroding magnesium implants

Fast escape of hydrogen from gas cavities around corroding magnesium implants

Direct Measurement of Nitric Oxide and Oxygen Partitioning into Liposomes and Low Density Lipoprotein

Carbonic Anhydrase II Binds to the Carboxyl Terminus of Human Band 3, the Erythrocyte Cl−/HCO3−Exchanger

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