scholarly journals Vm-related extracellular potentials observed in red blood cells

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Michael Pycraft Hughes ◽  
Emily J. Kruchek ◽  
Andrew D. Beale ◽  
Stephen J. Kitcatt ◽  
Sara Qureshi ◽  
...  
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Cancer Metastasis ◽  
Cell Function ◽  
Capacitive Coupling ◽  
Ion Concentration ◽  
Extracellular Potential ◽  
Ion Channel Regulation ◽  
Molecular Transporters ◽  
Voltage Gated Ion Channels

AbstractEven in nonexcitable cells, the membrane potential Vm is fundamental to cell function, with roles from ion channel regulation, development, to cancer metastasis. Vm arises from transmembrane ion concentration gradients; standard models assume homogeneous extracellular and intracellular ion concentrations, and that Vm only exists across the cell membrane and has no significance beyond it. Using red blood cells, we show that this is incorrect, or at least incomplete; Vm is detectable beyond the cell surface, and modulating Vm produces quantifiable and consistent changes in extracellular potential. Evidence strongly suggests this is due to capacitive coupling between Vm and the electrical double layer, rather than molecular transporters. We show that modulating Vm changes the extracellular ion composition, mimicking the behaviour if voltage-gated ion channels in non-excitable channels. We also observed Vm-synchronised circadian rhythms in extracellular potential, with significant implications for cell–cell interactions and cardiovascular disease.

scholarly journals THE ISOELECTRIC POINT OF RED BLOOD CELLS AND ITS RELATION TO AGGLUTINATION

1921 ◽  
Vol 3 (3) ◽  
pp. 309-323 ◽  
Author(s):  
Calvin B. Coulter
Keyword(s):  
Red Blood Cells ◽  
Isoelectric Point ◽  
Blood Cells ◽  
Inorganic Ions ◽  
Immune Serum ◽  
Ion Concentration ◽  
Normal Cells ◽  
Hydrogen Ion Concentration ◽  
Alkaline Side ◽  
Chlorine Ions

1. The movement of normal and sensitized red blood cells in the electric field is a function of the hydrogen ion concentration. The isoelectric point, at which no movement occurs, corresponds with pH 4.6. 2. On the alkaline side of the isoelectric point the charge carried is negative and increases with the alkalinity. On the acid side the charge is positive and increases with the acidity. 3. On the alkaline side at least the charge carried by sensitized cells is smaller and increases less rapidly with the alkalinity than the charge of normal cells. 4. Both normal and sensitized cells combine chemically with inorganic ions, and the isoelectric point is a turning point for this chemical behavior. On the acid side the cells combine with the hydrogen and chlorine ions, and in much larger amount than on the alkaline side; on the alkaline side the cells combine with a cation (Ba), and in larger amount than on the acid side. This behavior corresponds with that found by Loeb for gelatin. 5. The optimum for agglutination of normal cells is at pH 4.75, so that at this point the cells exist most nearly pure, or least combined with anion and cation. 6. The optimum for agglutination of sensitized cells is at pH 5.3. This point is probably connected with the optimum for flocculation of the immune serum body.

Redox imbalance of red blood cells impacts T lymphocyte homeostasis: implication in carotid atherosclerosis

2011 ◽  
Vol 106 (12) ◽  
pp. 1117-1126. ◽  
Author(s):  
Brigitta Buttari ◽  
Linda Petrone ◽  
Elisabetta Straface ◽  
Lucrezia Gambardella ◽  
Donatella Pietraforte ◽  
...  
Keyword(s):  
T Cell ◽  
T Lymphocytes ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Healthy Subjects ◽  
Carotid Atherosclerosis ◽  
Cell Function ◽  
Inflammatory Responses ◽  
Activated T Lymphocytes

SummaryOxidative stress and immune/inflammatory responses are key pathogenetic factors of atherosclerotic disease. In this contest, mechanisms that regulate survival and death of immune cells may be relevant. Previous studies have demonstrated that red blood cells (RBCs) are physiologically able to inhibit apoptosis and to promote proliferation of activated T lymphocytes from healthy subjects. The aim of the present study was to evaluate whether RBCs from patients with carotid atherosclerosis maintain their property to modulate T cell homeostasis. Peripheral blood lymphocytes (PBLs) obtained from healthy subjects were activated in vitro by phytohemagglutinin in the presence/absence of RBCs from patients with carotid atherosclerosis or of in vitro oxidised RBCs from healthy subjects. Levels of reactive oxygen species (ROS) and aging markers of RBCs as well as susceptibility to apoptosis of PBLs were evaluated by flow cytometry. PBL proliferation was evaluated by 3H-methyl-thymidine incorporation assay whereas secretion of cytokines, analysed in view of their key role in T cell function, was assessed by ELISA. Levels of ROS and phosphatidyl-serine externalisation, a sign of RBC aging, resulted significantly higher in RBCs from patients than in those from healthy subjects, whereas surface glycophorin A expression and reduced glutathione content did the opposite. Unlike RBCs obtained from healthy subjects, RBCs from patients and in vitro oxidised RBCs did not protect activated T lymphocytes from apoptosis. Hence, RBCs from patients with carotid atherosclerosis, probably due to their oxidative imbalance, impact T cell integrity and function. Our results suggest a new regulatory role for RBCs in atherosclerosis.

scholarly journals Using Redox Potential as a Feasible Marker for Banked Blood Quality and the State of Oxidative Stress in Stored Red Blood Cells

2020 ◽  
Author(s):  
Rodney C Daniels ◽  
Hyesun Jun ◽  
Robertson D Davenport ◽  
Maryanne M Collinson ◽  
Kevin R Ward
Keyword(s):  
Oxidative Stress ◽  
Redox Potential ◽  
Red Blood Cells ◽  
Healthy Volunteers ◽  
Blood Cells ◽  
Storage Time ◽  
Cell Function ◽  
Venous Blood ◽  
Functional Changes ◽  
Over Time

Abstract Background Stored Red Blood Cells (RBCs) may undergo oxidative stress over time, with functional changes affecting critical tasks such as oxygen delivery. Central to these changes are oxidation-reduction (redox) reactions and the redox potential (RP) that must be maintained for proper cell function. RP imbalance can lead to oxidative stress that may contribute to storage lesions and transfusion-related morbidities. Direct measures of RP may allow for evaluation of erythrocyte quality and enable corrections of RP prior to transfusion. Methods Multiple random RBC segments were tested, ranging in age from 5 to 40 days at 5 day intervals. RP was recorded by measuring open circuit potential of RBCs using novel nanoporous gold electrodes with Ag/AgCl reference. RP measures were also performed on peripheral venous blood samples from 10 healthy volunteers. RP measures were compared between groups of aged RBCs, and with volunteer blood. Results Stored RBCs show time-dependent increases in RP. There were significant differences in Day 5 RP compared to all other groups (p≤0.005), Day 10-15 vs ages ≥ Day 20 (p≤0.025), Day 20-25 vs Day 40 (p=0.039), and all groups compared to healthy volunteers. RP became more positive over time suggesting ongoing oxidation as RBCs age. However, storage time alone does not predict the ultimate RP value measured from a given unit.Conclusions There are significant differences in RP between freshly stored RBCs and all others, with RP becoming more positive over time. However, storage time alone does not predict RP, indicating RP screening may be important independent of storage time and may serve as a marker of RBC quality and state of oxidative stress. RP measurements may also provide a target by which to restore RP balance in aged pRBCs, improving their clinical effectiveness while reducing associated morbidities.

scholarly journals THE AGGLUTINATION OF RED BLOOD CELLS IN THE PRESENCE OF BLOOD SERA

1922 ◽  
Vol 4 (4) ◽  
pp. 403-409 ◽  
Author(s):  
Calvin B. Coulter
Keyword(s):  
Cell Membrane ◽  
Guinea Pig ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Ion Concentration ◽  
Red Cell ◽  
Free Medium ◽  
Optimal Point ◽  
Reaction Characteristic ◽  
Pig Serum

1. The addition of blood serum displaces the optimum for agglutination of red blood cells in a salt-free medium to the reaction characteristic of flocculation of the serum euglobulin. 2. This effect is not due merely to a mechanical entanglement of the cells by the precipitating euglobulin, since at reactions at which the latter is soluble it protects the cells from the agglutination which occurs in its absence. 3. A combination of some sort appears therefore to take place between sheep cells and sheep, rabbit, and guinea pig serum euglobulin, and involves a condensation of the serum protein upon the surface of the red cell. 4. At the optimal point for agglutination of persensitized cells both mid- and end-piece of complement combine with the cells. 5. Agglutination is closely related to an optimal H ion concentration in the suspending fluid, and probably of the cell membrane, and not to a definite reaction in the interior of the cell.

THE NUMBER OF RED BLOOD CELLS IN THE ISLETS OF LANGERHANS AS AN INDEX OF THE B CELL ACTIVITY

1960 ◽  
Vol XXXIV (IV) ◽  
pp. 611-618 ◽  
Author(s):  
Claes Hellerström ◽  
Sighild Westman ◽  
Ulla Zachrisson ◽  
Bo Hellman
Keyword(s):  
Blood Cell ◽  
Red Blood Cells ◽  
B Cell ◽  
Islets Of Langerhans ◽  
Red Blood Cell ◽  
Blood Cells ◽  
Cell Function ◽  
Cell Activity ◽  
Control Group ◽  
Cell Content

ABSTRACT The number of red blood cells in the islets of Langerhans has been considered as a useful index of the insulin synthesis, i. e. of the functional state of the B cells of the islets. It was found, however, that in starved rats which had only received water orally, the red blood cell content within the islets increased both absolutely as well as relatively to that in the exocrine parenchyma at the same time as the decrease in the B cell function as estimated by caryometry. There was a marked correlation, both in the control group and in the starved rats, between the red blood cell concentration in the exocrine and endocrine parts of the pancreas. The extent to which a rise in the functional activity of the A cells might have contributed to the increased content of red blood cells in the islets during starvation is discussed.

scholarly journals THE EFFECT OF VALENCY OF CATIONS AND ANIONS ON NEGATIVELY AND POSITIVELY CHARGED RED BLOOD CELLS

1924 ◽  
Vol 7 (2) ◽  
pp. 225-233 ◽  
Author(s):  
Jean Oliver ◽  
Leonard Barnard
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Cell Suspensions ◽  
Ion Concentration ◽  
Degree Of Hydrolysis ◽  
Red Cell ◽  
Hydrolysis Of ◽  
Positively Charged

1. Under comparable conditions, valency effect may be demonstrated with a suspension of red blood cells and the cations and anions of salts. 2. The valency of the cation determines the degree of the effect on negatively charged cells, the valency of the anion, the effect on positively charged cells. 3. Anomalies in valency effects with different salts and red cell suspensions are in part due to variations in H ion concentration, depending on the degree of hydrolysis of the salt.

scholarly journals HUBUNGAN ANTARA LAMA PENGGUNAAN ASPIRIN DENGAN NILAI AGREGASI TROMBOSIT PADA PASIEN HIPERTENSI DI RSUP PROF. DR. R. D. KANDOU MANADO

2014 ◽  
Vol 2 (2) ◽  
Author(s):  
Devianingsih Andikha Madao ◽  
A. E. Mongan ◽  
F. Manoppo
Keyword(s):  
Informed Consent ◽  
Blood Cell ◽  
Red Blood Cells ◽  
Red Blood Cell ◽  
Blood Cells ◽  
Cell Function ◽  
Cross Sectional ◽  
Ability Test ◽  
Correlation Test ◽  
Spearman’S Correlation

Abstract: The sufferer of hypertension around the world do not get medical treatment adequately. One of the hypertensive treatments is by the use of anti platelet hypertension aspirin. Aspirin on hypertension is to prevent any clinical manifestation from cardiovascular from happening. However, it could cause arterial wall hardening and decreases haemostasis ability. Test of red blood cell aggregation function is needed to monitor red blood cell function on hypertensive patient. Method: This study was analytical and employed cross sectional research design. The sample of the study were the sufferers of hypertensionfromaspirin usage treated in polyclinic of nephrology – hypertension and heart and cardiac polyclinic of internal diseasedivision in RSUP Prof. Dr. R. D. Kandou Manado. Patients included in inclusion criteria were 40 to 80 years old, proven to have hypertension by doctor, hypertension by aspirin usage, maleand female, and signed in informed consent. Result: There were 20 patients of hypertension by aspirin usage employed as sample in this study. Result of T test and spearman’s correlation test showed that there is no significant correlation between aspirin usage and the number of red blood cells’ aggregation (ADP 10µm p = 0,116, ADP 5µm p = 0,9). Conclusion: On hypertensive patients, there is no correlation between the period of aspirin usage and red blood cells’ aggregation. Keywords: hypertension, aspirin, red blood aggregation.   Abstrak: Penderita hipertensi di seluruh dunia tidak mendapatkan pengobatan secara adekuat. Salah satu pengobatan hipertensi dengan penggunaan antiplatelet hipertensi aspirin.Aspirin pada hipertensi berguna untuk mencegah terjadinya manifestasi klinis dari kardiovaskular, tetapi dapat menyebabkan terjadi pengerasan dinding arteri dan terjadinya penurunan kemampuan hemostasis.Tes fungsi agregasi trombosit diperlukan untuk memantau fungsi trombosit pada pasien hipertensi. Metode: Penelitian ini bersifat analitik dengan rancang penelitian cross sectional. Sampel penelitian adalah penderita hipertensi dengan penggunaan aspirin yang ada di Poliklinik Nefrologi – Hipertensi dan Poliklinik Jantung dan Pembuluh Darah bagian Ilmu Penyakit Dalam RSUP Prof. Dr. R. D. Kandou Manado. Pasien yang masuk kriteria inklusi yaitu usia 40-80 tahun, terbukti hipertensi oleh dokter, hipertensi dengan penggunaan aspirin, jenis kelamin laki-laki dan perempuan, dan menandatangani informed consent. Hasil: Terdapat 20 pasien hipertensi dengan penggunaan aspirin yang menjadi sampel dalam penelitian ini. Hasil uji T juga spearman’s correlation test didapatkan bahwa tidak terdapat hubungan yang signifikan antara penggunaan aspirin dengan nilai agregasi trombosit (ADP 10µm p = 0,116, ADP 5µm p = 0,9). Simpulan: Pada pasien Hipertensi, lama penggunaan aspirin dan nilai agregasi trombosit tidak mempunyai hubungan. Kata kunci: Hipertensi, aspirin, agregasi trombosit.

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