Sucrose feeding prevents changes in myosin isoenzymes and sarcoplasmic reticulum Ca2+-pump ATPase in pressure-loaded rat heart.

Pressure-overload due to banding of the abdominal aorta in rats for 10 weeks resulted in cardiac hypertrophy, redistribution of myosin isoenzymes and reduction in the sarcoplasmic reticulum (SR) Ca2+-stimulated ATPase activity. Administration of sucrose in the drinking water (0.8%, w/v) to rats prevented changes in myosin isoenzymes and SR Ca2+-stimulated ATPase in hypertrophied hearts. This beneficial effect of sucrose feeding with respect to remodeling of the subcellular organelles in the myocardium was not associated with any significant changes in plasma glucose or thyroid hormone levels. It is suggested that the prevention of subcellular changes in the hypertrophied hearts due to sucrose feeding may be due to a shift in fuel utilization by the myocardium.