Calcium-induced calcium release Calcium-induced calcium release Calcium-induced calcium release (CICR) describes a biological process whereby calcium is able to activate calcium release from intracellular Ca stores (e.g., endoplasmic reticulum or sarcoplasmic reticulum). Although CICR was first proposed for skeletal muscle in the 1970s, it is now known that CICR is unlikely to be its primary mechanism for activating SR calcium release. Instead, CICR is thought to be crucial for excitation-contraction coupling in cardiac muscle and it is now obvious that CICR is a widely occurring cellular signaling process present even in many non-muscle cells, e.g. in the insulin-secreting pancreatic beta cells and many
Nuclear calcium Nuclear calcium The concentration of calcium in the cell nucleus can increase in response to signals from the environment. Nuclear calcium is an evolutionary conserved potent regulator of gene expression that allows cells to undergo long-lasting adaptive responses. The 'Nuclear Calcium Hypothesis’ by Hilmar Bading describes nuclear calcium in neurons as an important signaling end-point in synapse-to-nucleus communication that activates gene expression programs needed for persistent adaptations. In the nervous system, nuclear calcium is required for long-term memory formation, acquired neuroprotection, and the development of chronic inflammatory pain. In the heart, nuclear calcium is important for the development of cardiac