The impact of RyR2 potentiation on myocardial function

LASCANO E,; NEGRONI J; VILA-PETROFF M; MATTIAZZI A

AMERICAN JOURNAL OF PHYSIOLOGY-HEART AND CIRCULATORY PHYSIOLOGY

AMER PHYSIOLOGICAL SOC

Lugar: Bethesda; Año: 2017

0363-6135

Lascano E, Negroni J, Petroff MV, Mattiazzi A. Impact of RyR2potentiation on myocardial function. Am J Physiol Heart Circ Physiol312: H000?H000, 2017. First published April 7, 2017; doi:10.1152/ajpheart.00855.2016.?This perspective attempts to shed light on anold and not yet solved controversy in cardiac physiology, i.e., theimpact of increasing ryanodine receptor (RyR)2 open probability onmyocardial function. Based on an already proven myocyte model, itwas shown that increasing RyR2 open probability results in a purelyshort-lived increase in Ca2 transient amplitude, and, therefore, itdoes not increase cardiac contractility. However, potentiation of RyR2activity permanently enhances fractional Ca2 release, shifting theintracellular Ca2 transient versus sarcoplasmic reticulum (SR) Ca2content curve to a new state of higher efficiency. This would allow theheart to maintain a given contractility despite a decrease in SR Ca2content, to enhance contractility if SR Ca2 content is simultaneouslypreserved or to successfully counteract the effects of a negativeinotropic intervention.