[Cytoskeletal proteins and heat shock proteins 27 under eccentric exercise of rats: effects of calcium L-type channel blockade].

It is known that during eccentric exercise the calcium accumulation and degradation of cytoskeletal proteins take place. This study was aimed to investigation into the role of baseline calcium accumulation in cytoskeletal degradation and the way of calcium inflow into skeletal muscle un- der conditions of eccentric exercise. Wister rats were divided into control (C), eccentric exercise (EE) (one set of downhill treadmill running (-16 degrees) at a speed of 20 m. min(-1) for 40 min) and eccentric exercise plus nifedipine administration (EEN) groups (with a daily supplementation of 6.25 mg/kg nifedipine in drinking water during two days). After a 24-hour post-exercise dystrophin, layer integrity and desmin level in m. soleus were declined in EE and didn't change in EEN gr. vs. C (p < 0.05). HSP27 were decreased in EEN in comparison with EE gr. (p < 0.05). Titin and nebullin were not changed after exercise. It seems that calcium L-type channel blocker attenuates or reduces the contraction-induced damage to cytoskeletal proteins.