Regulation of Calcium in Muscle Physiology
The physiological and biochemical roles of cells are controlled by calcium ions. Calcium acts as a second messenger in signal transduction pathways, in neurotransmitter release regulation, in fertilization and in all muscle cell type contraction. Calcium can act as a cofactor for many enzymes. The bone formation and the potential difference across excitable cell membranes are regulated by extracellular calcium. An abnormal change in the intracellular Ca 2+ concentration results in defective muscle contraction and/or relaxation, and any alteration in structural, metabolic or contractile proteins causes muscle diseases. Plasma membrane elements involved in membrane potentiation are induced by voltage and signal transduction. This potentiation leads to excitation of the cells followed by muscle contraction and relaxation. This cycle is called as excitation-contraction-relaxation cycle. Ca 2 + flux modified by mutations of membrane proteins causes severe pathophysiological effects in muscle. In this chapter, we reveal the different types of muscle functions and involvement of calcium channel in muscle physiology and disorders.
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Authors and Affiliations
- Department of Biochemistry, Rayalaseema University, Kurnool, AP, India Senthilkumar Rajagopal
- Center for Developmental Cardiology, Institute of Translational Medicine, Qingdao University, Qingdao, Shandong, China Murugavel Ponnusamy
- Senthilkumar Rajagopal