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标题：Identification and characterization of a newly recognized population of high-Na+, low-K+, low-density sickle and normal red cells
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作者：Robert M. Bookchin ; Zipora Etzion ; Martin Sorette 等
期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2000
卷号：97
期号：14
页码：8045-8050
DOI：10.1073/pnas.130198797
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：We describe a population of sickle cell anemia red cells (SS RBCs) ({approx}4%) and a smaller fraction of normal RBCs (<0.03%) that fail to dehydrate when permeabilized to K+ with either valinomycin or elevated internal Ca2+. The nonshrinking, valinomycin-resistant (val-res) fractions, first detected by flow cytometry of density-fractionated SS RBCs, constituted up to 60% of the lightest, reticulocyte-rich (R1) cell fraction, and progressively smaller portions of the slightly denser R2 cells and discocytes. R1 val-res RBCs had a mean cell hemoglobin concentration of {approx}21 g of Hb per dl, and many had an elongated shape like "irreversibly sickled cells," suggesting a dense SS cell origin. Of three possible explanations for val-res cells, failure of valinomycin to K+-permeabilize the cells, low co-ion permeability, or reduced driving K+ gradient, the latter proved responsible: Both SS and normal val-res RBCs were consistently high-Na+ and low-K+, even when processed entirely in Na-free media. Ca2+ + A23187 -induced K+-permeabilization of SS R1 fractions revealed a similar fraction of cal-res cells, whose 86Rb uptake showed both high Na/K pump and leak fluxes. val-res/cal-res RBCs might represent either a distinct erythroid genealogy, or an "end-stage" of normal and SS RBCs. This paper focuses on the discovery, basic characterization, and exclusion of artifactual origin of this RBC fraction. Many future studies will be needed to clarify their mechanism of generation and full pathophysiological significance.