Abstract
It is assumed that sodium ions, Na+, are involved in a Na-Ca exchange process at the β-cell membrane and in the mobilization of calcium ions, Ca2+, from intracellular stores4,5. Na-Ca exchange, which exchanges extracellular Na+ for intracellular Ca2+, has been observed in several cell types and has been characterized in detail in cardiac cells and membrane vesicles6. Na-Ca exchange depends on the electrochemical gradient of Na+ (and of Ca2+) across the cell membrane. This process is sensitive to changes in the membrane potential and the extracellular Na+ concentration, [Na+]o 6. If this process exists in β-cells, depolarization of the membrane will inhibit the exchange and enhance the intracellular Ca2+ concentration, [Ca2+]i, in the β-cells.
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© 1986 Plenum Press, New York
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Wolters, G.H.J., Vonk, M., Pasma, A. (1986). Relationship between Extracellular Na+ and the Total Ionized Ca2+ Content of Rat Pancreatic Islets. In: Atwater, I., Rojas, E., Soria, B. (eds) Biophysics of the Pancreatic β-Cell. Advances in Experimental Medicine and Biology, vol 211. Springer, Boston, MA. https://doi.org/10.1007/978-1-4684-5314-0_29
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DOI: https://doi.org/10.1007/978-1-4684-5314-0_29
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