A study was made comparing the effects of two oxidants--phenazine methosulfate (50-1500 microM)+10 mM ascorbate and t-butyl hydroperoxide (1-3 mM)--on the volume-related parameters of normal human red blood cells. Incubation with either oxidative system for 20-30 min resulted in red blood cell density and osmotic resistance distribution shifts. Treatment with the phenazine methosulfate+ascorbate system in the presence of Ca(2+) led to cell shrinking, with the maximum effect being more than 20%. In contrast, under the same conditions, t-BHP caused cell swelling by up to 15%. Modification of the suspending medium (Ca(2+) removing, clotrimazole addition, or enrichment with K(+)) modulated the redistribution effects, suggesting that they were mediated to some extent by Gardos channel activation. These findings are important for understanding how oxidants modulate RBC cation channels.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.bioelechem.2008.04.008 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Actin instability alters red blood cell mechanics and Piezo1 channel activity.
Biomech Model Mechanobiol
January 2025
CNR Istituto Officina Dei Materiali, Area Science Park Basovizza, S.S. 14, Km 163,5, 34149, Trieste, Italy.
The organization and dynamics of the spectrin-actin membrane cytoskeleton play a crucial role in determining the mechanical properties of red blood cells (RBC). RBC are subjected to various forces that induce deformation during blood microcirculation. Such forces also regulate membrane tension, leading to Piezo1 channel activation, which is functionally linked to RBC dehydration through calcium influx and subsequent activation of Gardos channels, ultimately resulting in variations in RBC volume.
View Article and Find Full Text PDFA new regulation mechanism for KCNN4, the Ca-dependent K channel, by molecular interactions with the Capump PMCA4b.
J Biol Chem
December 2024
Université Côte d'Azur, CNRS, Inserm, Institut Biologie Valrose, Nice, France; Laboratory of Excellence for RBC, LABEX GR-Ex, 75015, Paris, France. Electronic address:
KCNN4, a Ca-activated K channel, is involved in various physiological and pathological processes. It is essential for epithelial transport, immune system and other physiological mechanisms but its activation is also involved in cancer pathophysiology as well as red blood cell disorders (RBC). The activation of KCNN4 in RBC leads to loss of KCl and water, a mechanism known as the "Gardos effect" described seventy years ago.
View Article and Find Full Text PDFThe Calcium Homeostasis of Human Red Blood Cells in Health and Disease: Interactions of PIEZO1, the Plasma Membrane Calcium Pump, and Gardos Channels.
Annu Rev Physiol
October 2024
Physiological Laboratory, Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom; email:
Calcium ions mediate the volume homeostasis of human red blood cells (RBCs) in the circulation. The mechanism by which calcium ions affect RBC hydration states always follows the same sequence. Deformation of RBCs traversing capillaries briefly activates mechanosensitive PIEZO1 channels, allowing Ca2+ influx down its steep inward gradient transiently overcoming the calcium pump and elevating [Ca2+].
View Article and Find Full Text PDFPotassium dynamics in sickle cell anemia: clinical implications and pathophysiological insights.
Ann Med Surg (Lond)
October 2024
Department of Medical Laboratory Science, Kampala International University, Ishaka, Uganda.
Article Synopsis
- Potassium dynamics play a key role in sickle cell anemia (SCA), affecting disease complications like painful vaso-occlusive crises and hemolytic anemia due to dysregulated potassium transport and cellular dehydration.
- The loss of potassium leads to rigid sickle cells that cause blockages in blood vessels, worsening the symptoms of the disease and contributing to chronic hemolysis and anemia.
- Therapeutic strategies, including Gardos channel inhibitors like senicapoc and hydration therapy, are promising in managing SCA by improving potassium regulation and overall patient outcomes alongside standard treatments like hydroxyurea and blood transfusions.
Ammonium chloride-induced hypothermia is attenuated by transient receptor potential channel vanilloid-1, but augmented by ankyrin-1 in rodents.
Life Sci
June 2024
Department of Thermophysiology, Institute for Translational Medicine, Medical School, University of Pecs, Pecs H-7624, Hungary. Electronic address:
Aims: Systemic administration of ammonium chloride (NHCl), an acidifying agent used in human patients and experimental conditions, causes hypothermia in mice, however, the mechanisms of the thermoregulatory response to NHCl and whether it develops in other species remained unknown.
Main Methods: We studied body temperature (T) changes in rats and mice induced by intraperitoneal administration of NHCl after blockade of transient receptor potential vanilloid-1 (TRPV1) or ankyrin-1 (TRPA1) channels.
Key Findings: In rats, NHCl decreased T by 0.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!