“…Thus, it is likely that ET increased the [Ins(1,4,5)P 3 ] in the cytoplasm and nucleus and augmented CaTs in the two compartments through Ca 2+ release from Ins(1,4,5)P 3 receptors located in the SR and the nuclear envelope, respectively. Ins(1,4,5)P 3 -dependent Ca 2+ release from perinuclear stores into the nucleoplasm has been observed before in rat neonatal myocytes (Ibarra et al, 2004;Luo et al, 2007), in cat atrial myocytes (Zima et al, 2007) and in nuclei isolated from rat skeletal myotubes (Cardenas et al, 2005) or rat heart (Zima et al, 2007). The most elegant and direct evidence for independent Ins(1,4,5)P 3 -mediated nuclear Ca 2+ signalling comes from a recent study on permeabilised atrial myocytes and isolated cardiac nuclei (Zima et al, 2007).…”