Dissociation of hypertrophy and altered function in senescent rat myocardium
In the rat aging model functional and biochemical alterations of senescence are accompanied by myocardial hypertrophy. The studies described herein indicate that this hypertrophy (1) does not involve a concomitant alteration in myofibrillar ATPase activity, (2) is not the cause of prolonged contraction times, i.e., time-to-peak force and relaxation time observed in the senescent heart.
Key wordsadult aging rat myocardium isometric contraction isolated cardiac muscle myofibrillar ATPase cardiac hypertrophy chronic exercise
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