ABSTRACT: Development of heart failure is associated with an impairment of intracellular calcium handling. The precise mechanisms involved are still obscure. When membrane depolarization occurs, a small amount of extracellular calcium enters the intracellular milieu through the L-type channels. Such "trigger" calcium acts on specific receptors of the sarcoplasmic reticulum, that, in turn, according to the so-called calcium entry-calcium release mechanism, allows the release of a larger amount of calcium from the sarcoplasmic reticulum. Removal of calcium from the cytosol is the key event of the diastolic phase. Calcium removal from cytosol occurs through specific membrane pumps. Recent therapeutic approaches involving gene targeting of calcium pumps have yielded promising results. Specifically, increased levels of SERCA 2 in the myocardium have shown to enhance cardiac contractility under normal circumstances and in experimental heart failure. Future research is needed to confirm these findings in human heart failure.
Italian heart journal. Supplement: official journal of the Italian Federation of Cardiology 07/2000; 1(6):766-71.