Abstract
The sequence of events since the sarcolemma depolarization until the force generation by the myofilaments is called excitation-contraction (E-C) coupling. The autonomic action of a group of pacemaker cells generates action potentials which, reaching the myocytes, can drive a small intracellular Ca2+ influx by the activation of L-type channels and Na+/Ca+ exchangers (NCX) and initiate the …