Calcium ions (Ca2+) are key second messengers in a variety of eukaryotic cell signaling pathways, and they function in the regulation of diverse cellular processes. While it has become clear that Ca2+ stimulates many cellular processes, such as muscle contraction, cellular proliferation, gene expression, secretion of hormones and neurotransmitters, exocytosis, and chemotaxis, it has also been realized that Ca2+ is very toxic. Thus, the free intracellular Ca2+ concentration ([Ca2+]i) must be highly regulated to achieve a proper balance between Ca2+-mediated cell function and Ca2+-mediated cell death. The importance of intracellular calcium homeostasis is appreciated when one considers the number of subcellular compartments that function in regulating the [Ca2+]i as well as the diversity of cellular process that are controlled by Ca2+-signaling pathways. Each of these subcellular compartments can be targeted by chemicals or drugs, which can elicit an imbalance in intracellular Ca2+ homeostasis resulting in toxicity manifested as impaired cellular function or cell death. This chapter provides a basic understanding of the Ca2+ messenger system, Ca2+-activated proteases, such as calpains and PLA2, and their importance in cell injury.
|Original language||English (US)|
|Title of host publication||Cellular and Molecular Toxicology|
|Number of pages||22|
|State||Published - Aug 12 2010|
- Calcium channels
ASJC Scopus subject areas