Increased SR Ca2+ cycling contributes to improved contractile performance in SERCA2a-overexpressing transgenic rats

• Published in: Cardiovascular research 2005-09, Vol.67 (4), p.636-646
• Main Authors: MAIER, Lars S, WAHL-SCHOTT, Christian, PIESKE, Burkert, HORN, Wiebke, WEICHERT, Stefan, PAGEL, Christian, WAGNER, Stefan, DYBKOVA, Nataliya, MÜLLER, Oliver J, NÄBAUER, Michael, FRANZ, Wolfgang-M
• Format: Article
• Language: English
• Subjects: Animals; Animals, Genetically Modified; Biological and medical sciences; Blotting, Western - methods; Calcium - metabolism; Calcium Channels, L-Type - metabolism; Calcium-Transporting ATPases - metabolism; Cardiology. Vascular system; Electric Stimulation; Heart Failure - metabolism; In Vitro Techniques; Medical sciences; Myocardial Contraction - physiology; Myocytes, Cardiac - metabolism; Patch-Clamp Techniques; Rats; Sarcolemma - metabolism; Sarcoplasmic Reticulum - metabolism; Sarcoplasmic Reticulum Calcium-Transporting ATPases; Sodium-Calcium Exchanger - metabolism
• ISSN: 0008-6363; 1755-3245

Heart failure is associated with reduced function of sarcoplasmic reticulum (SR) Ca2+-ATPase (SERCA2a) but increased function of sarcolemmal Na+/Ca2+ exchanger (NCX), leading to decreased SR Ca2+ content and loss of frequency-potentiation of contractile force. We reported that SERCA2a-overexpression in transgenic rat hearts (TG) results in improved contractility. However, it was not clear whether TG have improved contractility due to frequency-dependent improved SR Ca2+ handling. Therefore, we characterized TG (n=35) vs. wild-type (WT) control rats (n=39) under physiological conditions (37 degrees C, stimulation rate