Increased Na+/Ca2+ exchanger expression/activity determines the point of inflection in the progression to heart failure of hypertensive rats.

RODRIGUEZ JS; VELEZ RUEDA JO; SALAS M; BECERRA R; DI CARLO MN; SAID M; VITTONE L; RINALDI G; PORTIANSKY EL; MUNDIÑA-WEILENMANN C; PALOMEQUE J; MATTIAZZI A.

PLOS ONE

PUBLIC LIBRARY SCIENCE

Lugar: San Francisco; Año: 2014 vol. 9 p. 1 - 10

1932-6203

Background. Spontaneous hypertensive rat (SHR) constitutes a genetic model widely used to study the natural evolution of hypertensive heart disease. Ca2+-handling alterations are known to occur in SHR. However, the putative modifications of Ca2+-handling proteins during the progression to HF are not well established. Moreover, the role of apoptosis in SHR is controversial. Methods and Results. We investigated intracellular Ca2+, Ca2+-handling proteins and apoptosis in SHR vs. control Wistar rats (W) from 3 to 15 months (mo). Changes associated with the transition to HF (i.e. lung edema and decrease in midwall fractional shortening), occurred at 15 mo in 38% of SHR (SHRF). In SHRF, twitch and caffeine-induced Ca2+ transients, significantly decreased relative to 6/9 mo and 15 mo without HF signs. This decrease occurred in association with a decrease in the time constant of caffeine-Ca2+ transient decay and an increase in Na+/Ca2+ exchanger (NCX) abundance (P