Effects of seven levels of chronic physical activity on the metabolic and morphologic characteristics of left ventricular myocardium of adult male albino rats were investigated.
Treatments included sedentary control; voluntary running; short-duration, high-intensity running; medium-duration, moderate-intensity running; long-duration, low-intensity running; electric stimulus control; and endurance swimming. Excluding the controls, the animals were trained 5 days per week for 8 consecutive weeks. Food and water were providedad libitum to them. Fifty-six animals comprised the final sample.
Histochemical techniques were used to evaluate the relative glycogen, fatty acid, SDH and LDH concentrations in the cardiac fibers. Each stain was measured objectively, using a photometer. A Hematoxylin and Eosin stain was employed to rate morphologic features. These sections were evaluated subjectively on the basis of presence or absence of lesions.
Physical training for 8 weeks was sufficient to produce metabolic adaptations in the rats. The trained animals gained 37.4 % less body weight than did the sedentary controls (P < 0.05). However, neither histochemical nor morphological changes had occurred to the hearts of these animals consequent to the 8 weeks training programs. Apparently, the myocardial tissues examined, from the trained animals, contain the enzymes, SDH and LDH, and the substrates, glycogen and fatty acids, in amounts greater than that needed to cope with the exercise stress afforded by these training programs.
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Bajusz, E., Raab, W.: Early metabolic aberrations through which epinephrine elicits myocardial necrosis. In: Raab, W., Ed., Prevention of ischemic heart disease: Principles and practice. Springfield: Charles C. Thomas 1966.
Barka, T., Anderson, P. J.: Histochemistry theory, practice and bibliography. New York: Harper and Bow 1963.
Bing, B. J.: Metabolic activity of the intact heart. Amer. J. Med.30, 679–691 (1961).
Burton, A. C.: Physiology and biophysics of the circulation. Chicago: Year Book Medical Publishers 1968.
Edgerton, V. R., Gerchman, L., Carrow, B.: Histochemical changes in rat skeletal muscle after exercise. Exp. Neurol.24, 110–123 (1969).
Gollnick, P. D., Hearn, G. R.: Lactic dehydrogenase activities of heart and skeletal muscle of exercised rats. Amer. J. Physiol.201, 694–696 (1961).
Gollnick, P. D., Struck, P. J., Bogyo, T. P.: Lactic dehydrogenase activities of rat heart and skeletal muscle after exercise and training. J. appl. Physiol.22, 623–627 (1967).
Gordon, E. E., Kowalski, K., Fritts, M.: Protein changes in quadriceps muscle of rat with repetitive exercise. Arch. phys. Med.48, 296–303 (1966).
Hearn, G. R., Wainio, W. W.: Succinic dehydrogenase activity of the heart and skeletal muscle of exercised rats. Amer. J. Physiol.185, 348–350 (1956).
Holczinger, L.: Histochemischer Nachweis freier Fettsäuren. Acta histochem. (Jena)8, 167–175 (1959).
Kitamura, K.: The role of sport activities in the prevention of cardiovascular malfunction. In: Kato, K., Ed., Proceedings of International Congress of Sport Sciences 1964. Tokyo: The Japanese Union of Sport Sciences 1966.
Letunov, S. P.: Effect of many years of sport activities on the cardiovascular system. In: Kato, K., Ed., Proceedings of International Congress of Sport Sciences 1964. Tokyo: The Japanese Union of Sport Sciences 1966.
- Manual of histologic and special staining techniques. Washington, D. C.: Armed Forces Institute of Pathology 1957.
Montoye, H. J., Ackerman, K., Van Huss, W. D., Nelson, R.: Effects of milk and training on swimming performance and organ weights in rats. Res. Quart.33, 104–110 (1962).
Opie, L. H.: Metabolism of the heart in health and disease. Part II. Amer. Heart J.77, 100–122 (1969).
Pearse, A. G. E.: Histochemistry: theoretical and applied. London: Churchill 1960.
Ruhling, R. O.: Histochemical observations on rat cardiac muscle following chronic exercise. Ph. D. Thesis, Michigan State University, 1970, available from University Microfilms, Inc., Ann Arbor. Michigan.
Rushmer, R. F.: Cardiovascular dynamics. Philadelphia: Saunders 1961.
Steinhaus, A. H.: Chronic effects of exercise. Physiol. Rev.13, 103–147 (1933).
Thomas, C. E.: The muscular architecture of the ventricles of hog and dog hearts. Amer. J. Anat.101, 17–57 (1957).
Van Huss, W. D., Heusner, W. W., Mickelsen, O.: Effects of prepubertal exercise on body composition. In: Franks, B. D., Ed., Exercise and fitness. Chicago: The Athletic Institute 1969.
Van Liere, E. J., Krames, B. B., Northup, D. W.: Differences in cardiac hypertrophy in exercise and in hypoxia. Circulat. Res.16, 244–248 (1965).
Wells, R. L., Heusner, W. W.: A controlled-running wheel for small animals. Lab. Anim. Sci.21, 904–910 (1971).
Wilkerson, J. E., Evonuk, E.: Changes in cardiac and skeletal muscle myosin ATPase activities after exercise. J. appl. Physiol.30, 328–330 (1971).
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Ruhling, R.O., van Huss, W.D., Heusner, W.W. et al. Histochemical and morphological observations on rat myocardium after exercise. Int. Z. Angew. Physiol. Einschl. Arbeitsphysiol. 31, 305–313 (1973). https://doi.org/10.1007/BF00693715