Mitochondrial calcium regulation during and following contractions in skeletal muscle

Abstract

In skeletal muscle, resting cytosolic Ca²⁺ concentration ([Ca²⁺]_cyto) homeostasis is exquisitely regulated by Ca²⁺ transport across the sarcolemmal, mitochondrial and sarcoplasmic reticulum (SR) membranes. Specifically, skeletal muscle contractile function is critically dependent on effective SR Ca²⁺ handling. However, more recent studies have revealed that mitochondria are essentially involved in [Ca²⁺]_cyto homeostasis during and following muscle contractions. We recently provided substantial support for the mitochondria as a major site for Ca²⁺ sequestration in skeletal muscle during recovery from fatiguing tetanic contractions under in vivo conditions. This review provides an overview of the role of skeletal muscle mitochondria in [Ca²⁺]_cyto regulation in vivo during and following muscle contractions.