Intracellular signaling following myocardial stretch: An autocrine/paracrine loop

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

REGULATORY PEPTIDES

Año: 2005 vol. 128 p. 211 - 220

0167-0115

The stretch of adult papillary muscle elicits a chain of autocrine/paracrine events in which the Na(+)/H(+) exchanger (NHE-1) activation is the central step. This activation is induced by a sequential angiotensin II-endothelin (Ang II-ET) 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 reverse potential of the Na(+)/Ca(2+) exchanger (NCX) thus inducing cell Ca(2+) influx that augments myocardial contractility. This increase in force represents the mechanical counterpart of the autocrine/paracrine mechanism triggered by stretch and has been called the slow force response (SFR) to stretch.