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Updated: Jun 22, 2026

Analysis of Cardiac Contractile Dysfunction and Ca2+ Transients in Rodent Myocytes
Published on: May 25, 2022
Exercise capacity is related to calcium transients in ventricular cardiomyocytes
Thales N Prímola-Gomes1, Lúcia A Campos, Sandra Lauton-Santos
1Department of Physiology and Biophysics, Biological Sciences Institute, Occupational Therapy School, Federal University of Minas Gerais, Av. Peter Henry Rolfs, Viçosa, Minas Gerais, 36570000, Brazil.
Abstract:
The aim of the present study was to evaluate the Ca2+ handling and contractility properties of cardiomyocytes isolated from rats with high intrinsic aerobic exercise capacity. Standard-performance (SP) and high-performance (HP) rats were categorized with a treadmill progressive exercise test according to the exercise time to fatigue (TTF). The SP group included rats with TTF between 16.63 and 46.57 min, and the HP group included rats with TTF>46.57 min. Isolated ventricular cardiomyocytes were dissociated from the hearts of SP and HP rats, and intracellular global Ca2+ ([Ca2+]i) transients were measured. The [Ca2+]i transient peak was increased in the HP group relative to the SP group (5.54+/-0.31 vs. 4.18+/-0.12 F/F0; P
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