TY - JOUR
T1 - Effects of varying intensity exercise on shortening and intracellular calcium in ventricular myocytes from streptozotocin (STZ)-induced diabetic rats
AU - Howarth, Frank Christopher
AU - Almugaddum, F. A.
AU - Qureshi, M. A.
AU - Ljubisavijevic, M.
PY - 2008
Y1 - 2008
N2 - This study examined the influence of two intensities of exercise on ventricular myocyte shortening and intracellular calcium in the streptozotocin (STZ)-induced diabetic rat. Animals were divided into four groups: control sedentary (CS), diabetic sedentary (DS), diabetic light exercise (DLE; 5 × 30 min/week, 9 m/min) and diabetic moderate exercise (DME; 5 × 30 min/week, 18 m/min) and the exercise programme started 2 months after STZ treatment. Time to peak (TPK) shortening was prolonged in myocytes from DS (112.1 ± 2.5 ms) compared to CS (98.1 ± 2.1 ms) rats and was not additionally altered by either light (117.0 ± 2.1 ms) or moderate (115.4 ± 2.0 ms) exercise. TPK of the Ca2+ transient was not significantly altered by STZ treatment (69.4 ± 2.4 ms) but was prolonged by light (79.8 ± 3.5 ms) and moderate (76.6 ± 2.9 ms) exercise compared to CS (65.5 ± 2.7 ms). Data from this study suggest that the chosen intensities of exercise were ineffective in modulating the dynamics of cardiac muscle contraction and reversing the deleterious effects of diabetes on heart-muscle contraction.
AB - This study examined the influence of two intensities of exercise on ventricular myocyte shortening and intracellular calcium in the streptozotocin (STZ)-induced diabetic rat. Animals were divided into four groups: control sedentary (CS), diabetic sedentary (DS), diabetic light exercise (DLE; 5 × 30 min/week, 9 m/min) and diabetic moderate exercise (DME; 5 × 30 min/week, 18 m/min) and the exercise programme started 2 months after STZ treatment. Time to peak (TPK) shortening was prolonged in myocytes from DS (112.1 ± 2.5 ms) compared to CS (98.1 ± 2.1 ms) rats and was not additionally altered by either light (117.0 ± 2.1 ms) or moderate (115.4 ± 2.0 ms) exercise. TPK of the Ca2+ transient was not significantly altered by STZ treatment (69.4 ± 2.4 ms) but was prolonged by light (79.8 ± 3.5 ms) and moderate (76.6 ± 2.9 ms) exercise compared to CS (65.5 ± 2.7 ms). Data from this study suggest that the chosen intensities of exercise were ineffective in modulating the dynamics of cardiac muscle contraction and reversing the deleterious effects of diabetes on heart-muscle contraction.
KW - Cardiac muscle
KW - Diabetes mellitus
KW - Exercise training
KW - Ventricular myocytes
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U2 - 10.1007/s11010-008-9844-z
DO - 10.1007/s11010-008-9844-z
M3 - Article
C2 - 18553174
AN - SCOPUS:53149153156
SN - 0300-8177
VL - 317
SP - 161
EP - 167
JO - Molecular and cellular biochemistry
JF - Molecular and cellular biochemistry
IS - 1-2
ER -