The control of calcium signaling in the heart

Abstract

Work on the role of calcium in the heart began in the nineteenth century with Ringer’s demonstration that calcium is essential for cardiac contraction. This article provides a brief overview of the regulation of cardiac calcium signalling. Contraction results from the systolic rise of Ca concentration (the Ca transient). This occurs by the process of calcium induced Ca release in which Ca entry into the cell results in the opening of the sarcoplasmic reticulum Ca release channel (Ryanodine Receptor) releasing a much larger quantity of Ca into the cytoplasm. The Ca concentration in the sarcoplasmic reticulum is a major factor determining the amplitude of the Ca transient. The remainder of the article discusses how sarcoplasmic reticulum Ca content is regulated and the consequences this has for regulation of systolic Ca.

Keywords: heart; calcium; sarcoplasmic reticulum, Ryanodine Receptor