Dissociation of hypertrophy and altered function in senescent rat myocardium

  • E. G. Lakatta

Summary

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 words

adult aging rat myocardium isometric contraction isolated cardiac muscle myofibrillar ATPase cardiac hypertrophy chronic exercise 

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References

  1. 1.
    Alpert, N. R., H. H. Gale, N. Taylor: The effect of age on contractile Protein ATPase activity and the velocity of shortening. In: Factors Influencing Myocardial Contractility, edited by R. D. Tanz, F. Kavaler, and J. Roberts, Academic Press, New York, pp. 127–133 (1967).Google Scholar
  2. 2.
    Bhatnagar, G. M., G. D. Walford, E. S. Beard, E. G. Lakatta: Dissociation of time to peak force (TPF) and myofibrillar ATPase activity (MF-ATPase) with aging of the myocardium (Abstract). Federation Proc. 41, 1513 (1982).Google Scholar
  3. 3.
    Chesky, J. A., M. Rockstein: Reduced myocardial actomyosin adenosine triphosphatase activity in the ageing male Fischer rat. Cardiovasc. Res. 11, 242–246 (1977).PubMedCrossRefGoogle Scholar
  4. 4.
    Effron, M. B., G. Ruano-Arroyo, H. A. Spurgeon, G. M. Bhatnagar, E. G. Lakatta: Hyperthyroid state reverses prolonged contraction in rat cardiac muscle without altering myofibrillar ATPase activity (Abstract). Federation Proc. 42, number 3, p. 465 (1983).Google Scholar
  5. 5.
    Heller, L. J., W. V. Whitehorn: Age-associated alteration in myocardial contractile properties. Amer. J. Physiol. 22, 1613–1619 (1972).Google Scholar
  6. 6.
    Jacob, R., G. Ebrecht, A. Kammereit, I. Medugoras, M. F. Wendt-Gallitelli: Myocardial function in different models of cardiac hypertrophy. An attempt at correlating mechanical, biochemical, and morphological parameters. Basic Res. Cardiol. 72, 160–167 (1977).PubMedCrossRefGoogle Scholar
  7. 7.
    Klotz, C., B. Swynghedauw, H. Mendes, F. Marotte, J. J. Leger: Evidence for new forms of cardiac myosin heavy chains in mechanical heart overloading and in ageing. Eur. J. Biochem. 115, 415–421 (1981).PubMedCrossRefGoogle Scholar
  8. 8.
    Korecky, B.: The effects of load, internal environment and age on cardiac mechanics (Abstract). J. Mol. Cell. Cardiol. 11, Suppl. 1, 33 (1979).Google Scholar
  9. 9.
    Lakatta, E. G.: Alterations in the cardiovascular system that occur in advanced age. Federation Proc. 38, 163–167 (1979).Google Scholar
  10. 10.
    Lakatta, E. G., F. C. P. Yin: Myocardial aging: functional alterations and related cellular mechanisms. Amer. J. Physiol. 242 (Heart Circ. Physiol. 11), H927–941 (1982).PubMedGoogle Scholar
  11. 11.
    Mercadier, J.-J., A.-M. Lompre, C. Weisnewsky, J.-L. Samuel, J. Bercovici, B. Swynghedauw, K. Schwartz: Myosin isoenzymic changes in several models of rat cardiac hypertrophy. Circulát. Res. 49, 525–532 (1981).PubMedGoogle Scholar
  12. 12.
    Resink, T. J., W. Gevers: Altered adenosine triphosphatase activities of natural actomyosin from rat hearts perfused with isoprenaline and ouabain. Cell Calcium 2, 105–123 (1981).CrossRefGoogle Scholar
  13. 13.
    Solaro, R. J., R. M. Wise, J. S. Shiner, F. N. Briggs: Calcium requirements of cardiac myofibrillar activation. Circulát. Res. 34, 525–530 (1974).PubMedGoogle Scholar
  14. 14.
    Spurgeon, H. A., D. K. Ingram, E. G. Lakatta: Long-term food restriction causes cardiac atrophy but does not alter rat cardiac muscle performance (Abstract). Federation Proc. 42, number 3, p. 466 (1983).Google Scholar
  15. 15.
    Spurgeon, H. A., M. F. Steinbach, E. G. Lakatta: Chronic exercise prevents characteristic age-related changes in rat cardiac contraction. Amer. J. Physiol. (in press) (1983).Google Scholar
  16. 16.
    Wei, J. Y., H. A. Spurgeon, E. G. Lakatta: Transmembrane action potential duration and contractile activation are lengthened in cardiac muscle of senescent rats (Abstract). Clin. Res. 28, 619 (1980).Google Scholar
  17. 17.
    Weisfeldt, M. L., W. A. Loeven, N. W. Shock: Resting and active mechanical properties of trabeculae carneae from aged male rats. Amer. J. Physiol. 220, 1921–1927 (1971).PubMedGoogle Scholar
  18. 18.
    Yin, F. C. P., H. A. Spurgeon, K. Rakusan, M. L. Weisfeldt, E. G. Lakatta: Use of tibial length to quantify cardiac hypertrophy: application in the aging rat. Amer. J. Physiol. 243 (Heart Circ. Physiol. 12), H941–947, 1982.PubMedGoogle Scholar
  19. 19.
    Yin, F. C. P., H. A. Spurgeon, M. L. Weisfeldt, E. G. Lakatta: Mechanical properties of myocardium from hypertrophied rat hearts. A comparison between hypertrophy induced by senescence and by aortic banding. Circulát. Res. 46, 292–300 (1980).Google Scholar

Copyright information

© Dr. Dietrich Steinkopff Verlag, GmbH & Co. KG, Darmstadt 1983

Authors and Affiliations

  • E. G. Lakatta
    • 1
  1. 1.Gerontology Research Center, National Institute on AgingNational Institutes of HealthBaltimore, MarylandUSA

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