Premium
Exercise reduces the maximal rate of rise of the calcium transient in rat cardiomyocytes
Author(s) -
Davidson Christopher James,
Baum Kerry R,
Spitzer Kenneth W,
Bridge John HB
Publication year - 2006
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.20.5.a1448-c
Subject(s) - calcium , treadmill , medicine , chemistry , endurance training , calcium in biology , endocrinology , cardiology
Objective We examined the effect of endurance run training on macroscopic calcium release in ventricular cardiomyocytes isolated from control (CON) and treadmill‐trained (TR) female Sprague‐Dawley (SD) rats. Methods Female SD rats were exercised on a treadmill 5 days per week for at least 20 weeks at progressive speeds up to 40 m/min. Cardiomyocytes were isolated enzymatically and loaded with Fluo‐4 dye. Action potentials were recorded at 1 Hz. Line scan diagrams of calcium transients were recorded with a confocal microscope. Results Maximal rate of rise of the calcium transient was significantly reduced in the exercise trained animals [5.4±0.6 μM/sec TR vs. 7.9±1.0 μM/sec CON; P < 0.05]. Conclusion Endurance exercise modified the calcium transient in cardiomyocytes. This suggests fundamental alteration in the mechanism of excitation‐contraction coupling. This work was supported by the Richard A. and Nora Eccles Harrison endowment and awards from the Nora Eccles Treadwell Foundation and the National Institutes of Health Research Grants HL62690 and HL70828.