Dataset Information

Enhanced Ca²⁺ influx in mechanically distorted erythrocytes measured with ¹⁹F nuclear magnetic resonance spectroscopy.

ABSTRACT: We present the first direct nuclear magnetic resonance (NMR) evidence of enhanced entry of Ca²⁺ ions into human erythrocytes (red blood cells; RBCs), when these cells are mechanically distorted. For this we loaded the RBCs with the fluorinated Ca²⁺ chelator, 1,2-bis(2-amino-5-fluorophenoxy)ethane-N,N,N',N'-tetraacetic acid (5FBAPTA), and recorded ¹⁹F NMR spectra. The RBCs were suspended in gelatin gel in a special stretching/compression apparatus. The 5FBAPTA was loaded into the cells as the tetraacetoxymethyl ester; and ¹³C NMR spectroscopy with [1,6-¹³C]D-glucose as substrate showed active glycolysis albeit at a reduced rate in cell suspensions and gels. The enhancement of Ca²⁺ influx is concluded to be via the mechanosensitive cation channel Piezo1. The increased rate of influx brought about by the activator of Piezo1, 2-[5-[[(2,6-dichlorophenyl)methyl]thio]-1,3,4-thiadiazol-2-yl]-pyrazine (Yoda1) supported this conclusion; while the specificity of the cation-sensing by 5FBAPTA was confirmed by using the Ca²⁺ ionophore, A23187.

SUBMITTER: Kuchel PW

PROVIDER: S-EPMC7881017 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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Publications

Enhanced Ca2+ influx in mechanically distorted erythrocytes measured with 19F nuclear magnetic resonance spectroscopy.

Kuchel Philip W PW Romanenko Konstantin K Shishmarev Dmitry D Galvosas Petrik P Cox Charles D CD

Scientific reports 20210212 1

We present the first direct nuclear magnetic resonance (NMR) evidence of enhanced entry of Ca2+ ions into human erythrocytes (red blood cells; RBCs), when these cells are mechanically distorted. For this we loaded the RBCs with the fluorinated Ca2+ chelator, 1,2-bis(2-amino-5-fluorophenoxy)ethane-N,N,N',N'-tetraacetic acid (5FBAPTA), and recorded 19F NMR spectra. The RBCs were suspended in gelatin gel in a special stretching/compression apparatus. The 5FBAPTA was ...[more]

PMID: 33580124

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Dataset Information

Enhanced Ca²⁺ influx in mechanically distorted erythrocytes measured with ¹⁹F nuclear magnetic resonance spectroscopy.

Publications

Enhanced Ca<sup>2+</sup> influx in mechanically distorted erythrocytes measured with <sup>19</sup>F nuclear magnetic resonance spectroscopy.

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