Ion channels in human erythroblasts: Modulation by erythropoietin

Joseph Y. Cheung, Mary Beth Elensky, Ulrike Brauneis, Russell C. Scaduto, Laurie L. Bell, Douglas L. Tillotson, Barbara A. Miller

Research output: Contribution to journalArticle

32 Scopus citations

Abstract

To investigate the mechanism of intracellular Ca2+ ([Cail) increase in human burst-forming unit-erythroid-derived erythroblasts by erythropoietin, we measured [Cai] with digital video imaging, cellular phosphoinositides with high performance liquid Chromatograph), and plasma membrane potential and currents with whole cell patch clamp. Chelation of extracellular free Ca2+ abolished [Cai] increase induced by erythropoietin. In addition, the levels of inositol-1,4,5-trisphosphate did not increase in erythropoietin-treated erythroblasts. These results indicate that in erythropoietin-stimulated cells, Ca2+ influx rather than intracellular Ca2+ mobilization was responsible for [Cai] rise. Both Ni2+ and moderately high doses of nifedipine blocked [Cai] increase, suggesting involvement of ion channels. Resting membrane potential in human erythroblasts was -10.9±1.0 mV and was not affected by erythropoietin, suggesting erythropoietin modulated a voltage-independent ion channel permeable to Ca2+. No voltage-dependent ion channel but a Ca2+-activated K+ channel was detected in human erythroblasts. The magnitude of erythropoietin-induced [Cai] increase, however, was insufficient to open Ca2+-activated K+ channels. Our data suggest erythropoietin modulated a voltage-independent ion channel permeable to Ca2+, resulting in sustained increases in [Cai].

Original languageEnglish (US)
Pages (from-to)1850-1856
Number of pages7
JournalJournal of Clinical Investigation
Volume90
Issue number5
DOIs
StatePublished - Nov 1992

All Science Journal Classification (ASJC) codes

  • Medicine(all)

Fingerprint Dive into the research topics of 'Ion channels in human erythroblasts: Modulation by erythropoietin'. Together they form a unique fingerprint.

  • Cite this

    Cheung, J. Y., Elensky, M. B., Brauneis, U., Scaduto, R. C., Bell, L. L., Tillotson, D. L., & Miller, B. A. (1992). Ion channels in human erythroblasts: Modulation by erythropoietin. Journal of Clinical Investigation, 90(5), 1850-1856. https://doi.org/10.1172/JCI116061