Diastolic Calcium Release Controls the Beating Rate of Rabbit Sinoatrial Node Cells: Numerical Modeling of the Coupling Process

From: Biophysical Journal | Date: April 1, 2004| Author: Bogdanov, Konstantin Y; Lakatta, Edward G; Stern, Michael D; Vinogradova, Tatiana M; Maltsev, Victor A | Copyright information

ABSTRACT Recent studies employing Ca^sup 2+^ indicators and confocal microscopy demonstrate substantial local Ca^sup 2+^ release beneath the cell plasma membrane (subspace) of sinoatrial node cells (SANCs) occurring during diastolic depolarization. Pharmacological and biophysical experiments have suggested that the released Ca^sup 2+^ interacts with the plasma membrane via the ion current (I^sub NaCa^) produced by the Na^sup +^/Ca^sup 2+^ exchanger and constitutes an important determinant of ...

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