SLN and heart failure: While in rodents a decrease in SR calcium content (Saba et al., 2005) is associated with reduced SERCA, PLB, and sarcolipin expression (Shanmugam et al., 2011), a somewhat different story predominates in large mammals in which atrial SR calcium content increases in heart failure (Yeh et al., 2008; Clarke et al., 2015; Aistrup et al., 2017) despite decreased calcium reuptake by SERCA (Clarke et al., 2015; Hohendanner et al., 2016).