The Na+/H+ exchanger as the main protagonist following myocardial stretch: The Anrep effect and myocardial hypertrophy.

CINGOLANI HE; AIELLO EA; PÉREZ NG; ENNIS IL; CAMILIÓN DE HURTADO MC

“Mechanosensitivity in Cells and Tissues”

Año: 2005; p. 271 - 290

The stretch of cardiac muscle elicits a chain of autocrine/paracrine events in which the Na+/H+ exchanger activation is the central step. This activation is induced by a sequential angiotensin II-endothelin release and results in an increase in intracellular Na+ [Na+]i without significant changes in intracellular pH. The increase in [Na+]i negatively shifts the reversal potential of the Na+/Ca2+ exchanger, thus inducing cell Ca2+ influx that augments myocardial contractility. This increase in force, which represents the mechanical counterpart of the autocrine/paracrine mechanism triggered by stretch and that has been called the slow force response to stretch (SFR), provides an explanation for the Anrep effect. In this article we discuss the potential link between the mechanisms involved in the Anrep effect and the development of cardiac hypertrophy.