Calcium homeostasis behavior and cardiac function on left ventricular remodeling by pressure overload

Sarcoplasmic reticulum Ca2+-ATPase (SERCA2a) and sarcolemmal Na+/Ca2+ exchanger (NCX1) structures are involved in heart cell Ca2+ homeostasis. Previous studies have shown discrepancies in their function and expression in heart failure. The goal of this study was to evaluate heart function and hypert...

Descripción completa

Detalles Bibliográficos
Autores: Mazeto, I. F. S. [UNESP], Okoshi, K. [UNESP], Silveira, C. F. S. M. P. [UNESP], Sant'Ana, P. G. [UNESP], Silva, V. L. da [UNESP], Mota, G. A. F. [UNESP], Souza, S. L. B. de [UNESP], Vileigas, D. F. [UNESP], Padovani, C. R. [UNESP], Cicogna, A. C. [UNESP]
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2021
País:Brasil
Institución:Universidade Estadual Paulista (UNESP)
Repositorio:Repositório Institucional da UNESP
Idioma:inglés
OAI Identifier:oai:repositorio.unesp.br:11449/210068
Acceso en línea:http://dx.doi.org/10.1590/1414-431X202010138
http://hdl.handle.net/11449/210068
Access Level:acceso abierto
Palabra clave:Aortic stenosis
Diastolic dysfunction
Calcium-handling proteins
Rats
Pressure
Descripción
Sumario:Sarcoplasmic reticulum Ca2+-ATPase (SERCA2a) and sarcolemmal Na+/Ca2+ exchanger (NCX1) structures are involved in heart cell Ca2+ homeostasis. Previous studies have shown discrepancies in their function and expression in heart failure. The goal of this study was to evaluate heart function and hypertrophied muscle Ca2+-handling protein behavior under pressure overload. Twenty male Wistar rats were divided into two groups: Aortic stenosis (AoS), induced by a clip placed at the beginning of the aorta, and Control (Sham). After 18 weeks, heart function and structure were evaluated by echocardiogram. Myocardial function was analyzed by isolated papillary muscle (IPM) at basal condition and Ca2+ protein functions were evaluated after post-pause contraction and blockage with cyclopiazonic acid in IPM. Ca2+-handling protein expression was studied by western blot (WB). Echocardiogram showed that AoS caused concentric hypertrophy with enhanced ejection fraction and diastolic dysfunction inferred by dilated left atrium and increased relative wall thickness. IPM study showed developed tension was the same in both groups. AoS showed increased stiffness revealed by enhanced resting tension, and changes in Ca2+ homeostasis shown by calcium elevation and SERCA2a blockage maneuvers. WB revealed decreased NCX1, SERCA2a, and phosphorylated phospholambam (PLB) on serine-16 in AoS. AoS had left ventricular hypertrophy and diastolic dysfunction compared to Sham; this could be related to our findings regarding calcium homeostasis behavior: deficit in NCX1, SERCA2a, and phosphorylated PLB on serine-16.