Abstract
The possible contribution of mitochondrial Ca2+ accumulation and release to contractile phenomena has been investigated. Two intracellular fractions of Ca2+ sequestration can be identified in cardiac myocytes, one ascribed to mitochondria. Two modes of Ca2+ transport exist within the mitochondrial fraction, one dependent upon mitochondrial respiration and the other upon extramitochondrial [Na+]. Experiments with trabeculae show that under appropriate conditions, the rate of relaxation and the amount of tension developed is dependent on these two modes of Ca2+ transport. A model is presented quantifying the contribution of the mitochondria to relaxation.
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Fry, C.H., Miller, D.J., Harding, D.P. et al. The contribution of mitochondrial calcium ion exchange to relaxation of tension in cardiac muscle. Mol Cell Biochem 89, 127–133 (1989). https://doi.org/10.1007/BF00220764
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DOI: https://doi.org/10.1007/BF00220764