Fig. 10. Atrial myocyte Ca²⁺ signalling machinery. The cartoon depicts the arrangement of atrial myocyte-specific components of the Ca²⁺ signalling toolkit that contribute to the generation and modulation of atrial myocyte Ca²⁺ signals. The green band in the cartoon designates the boundary that the subsarcolemmal Ca²⁺ signal has to cross in order to recruit central RyRs and trigger contraction.