Lusitropic effect

Lusitropic effects refer to the ability of the heart's muscle tissue (myocardium) to relax during the diastolic phase, allowing efficient filling of the ventricles. Positive lusitropy denotes improved or faster relaxation, essential for adaptation to increased heart rate and demand, primarily mediated by molecular processes involving calcium reuptake into the sarcoplasmic reticulum via SERCA2a, phosphorylation of phospholamban, and signaling through β-adrenergic receptors. Dysregulation of lusitropic processes contributes significantly to heart failure, diastolic dysfunction, and cardiomyopathies, making molecular regulators of lusitropy important therapeutic targets[1][2][3][4][5][7][8].

Other names

Lusitropydiastolic relaxation effectmyocardial relaxation

Enhancement of SERCA2a activity (improved calcium uptake into sarcoplasmic reticulum) Phosphorylation of phospholamban (relieves inhibition of SERCA2a) Beta-adrenergic signaling (cAMP/PKA pathway increases rate of relaxation) Calcium sensitization of myofilaments Inhibition of late sodium current (reduces intracellular calcium overload) Nitroxyl-mediated protein modification (enhances Ca2+ handling)