Summary
In rats exposed to a simulated high altitude of 3500 m for their whole prenatal and postnatal life a severe cardiac hypertrophy develops. In rats born and first staying 5 weeks at sea level and then being exposed to simulated high altitude, only a unilateral right cardiac hypertrophy occurs. In both groups nutritional coronary blood flow was estimated in left ventricle, right ventricle, and septum and was compared with control animals of similar age. Coronary blood flow was measured at hypoxia in all groups. At first cardiac output was determined by the Fick principle, then86Rb was applied and the animals were killed after 55 sec. Activity of86Rb was measured in both cardiac ventricles and septum and the fractional uptake was calculated. According to Sapirstein (1956, 1958) the distribution of86Rb follows the distribution of cardiac output and from both these data the nutritional blood flow to the parts of the heart may be estimated.
Cardiac output was similar in rats exposed to simulated high altitude later in life (“newcomers”) and in control animals, but it was significantly lower in rats born in the low pressure chamber (“natives”).
Fractions of cardiac output supplying cardiac ventricles and septum in rats from both hypoxic groups were significantly higher than in control animals. In the “natives” they were significantly higher than in the “newcomers”. The fractions of cardiac output in both “newcomers” and “natives” remained significantly higher than those of the control animals, also when calculated per gram of heart tissue.
Nutritional coronary blood flow (in ml/min) was higher in both ventricles and septum of the “newcomers” and in the right ventricle of the “natives”, and lower in the septum of the “natives”, when compared with control animals. Coronary blood flow per gram of heart tissue (in ml/min·g) was significantly higher in all cardiac parts of the “newcomers”, but it was about the same in all cardiac parts of the “natives” when compared with controls.
The importance of observed changes concerning myocardial tissue oxygenation is analyzed by using Krogh's cylindrical tissue model.
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References
Adair, G. S.: The hemoglobin system. VI. The oxygen dissociation curve of hemoglobin. J. biol. Chem.63, 529–545 (1925)
Altman, P. L., Dittmer, D. S., Eds.: Metabolism. Biological Handbooks. Bethesda, Maryland: Federation of American Societies for Experimental Biology 1968
Chiodi, H.: Action of high altitude chronic hypoxia on newborn animals. In: The physiological effects of high altitude, W. H. Weihe, ed., pp. 97–113. Oxford: Pergamon Press 1964
Chiodi, H.: Study of possible mechanism of fatty liver of chronic hypoxic suckling rats. Amer. J. Physiol.218, 92–94 (1970)
Chiodi, H. P., Bass, R.: Hypoxic liver degeneration in suckling rats. Fed. Proc.28, 1080–1084 (1969)
Doll, E., Keul, J., Steim, H., Maiwald, Chr., Reindell, H.: Über den Stoffwechsel des Herzens bei Hochleistungssportlern. II. Sauerstoff- und Kohlensäuredruck, pH, Standardbikarbonat und Base Excess im koronarvenösen Blut in Ruhe, während und nach körperlicher Arbeit. Z. Kreis.-Forsch.3, 248–262 (1966)
Fulton, R. M., Hutchinson, E. C., Jones, A. M.: Ventricular weight in cardiac hypertrophy. Brit. Heart J.14, 413–420 (1952)
Grandtner, M., Turek, Z., Kreuzer, F.: Cardiac hypertrophy in the first generation of rats native to simulated high altitude. Muscle fiber diameter and diffusion distance in the right and left ventricle. Pflügers Arch.350, 241–248 (1974)
Hort, W.: Quantitative Untersuchungen über die Capillarisierung des Herzmuskels im Erwachsenen- und Greisenalter, bei Hypertrophie und Hyperplasie. Virchows Arch. path. Anat.327, 560–576 (1955)
Hurtado, A.: The influence of high altitude on physiology. In: CIBA Foundation Symposium High Altitude Physiology: Cardiac and respiratory aspects, R. Porter and J. Knight, Eds., pp. 3–8. Edinburgh-London: Churchill Livingstone 1971
Krogh, A.: The anatomy and physiology of capillaries. New Haven: Yale University Press 1922
Mendell, P. L., Hollenberg, N. K.: Cardiac output distribution in the rat: comparison of rubidium and microsphere methods. Amer. J. Physiol.221, 1617–1620 (1971)
Monge, C.: Acclimatization in the Andes. Baltimore: The Johns Hopkins Press 1948
Moret, P., Covarrubias, E., Coudert, J., Duchosal, F.: La circulation coronaire et le métabolisme du myocarde aux hautes altitudes (Hauts Plateaux des Andes). Schweiz. med. Wschr.100, 2186–2189 (1970)
Moret, P., Covarrubias, E., Coundert, J., Duchosal, F.: Cardiocirculatory adaptation to chronic hypoxia. I. Comparative study of coronary flow, myocardial oxygen consumption and efficiency between sea level and high altitude residents. Acta cardiol. (Brux.)27, 283–305 (1972)
Myers, W. W., Honig, C. R.: Amount and distribution of Rb86 transported into myocardium from ventricular lumen. Amer. J. Physiol.211, 739–745 (1966)
Petropoulos, E. A., Vernadakis, A., Timiras, P. S.: Nucleic acid content in developing rat brain after prenatal and/or neonatal exposure to high altitude. Fed. Proc.28, 1001–1005 (1969)
Petropoulos, E. A., Vernadakis, A., Timiras, P. S.: Neurochemical changes in rats subjected neonatally to high altitude and electroshock. Amer. J. Physiol.218, 1351–1356 (1970)
Petropoulos, E. A., Dalal, K. B., Timiras, P. S.: Effect of high altitude on myelinogenesis in brain of the developing rat. Amer. J. Physiol.223, 951–957 (1972)
Rakušan, K.: Oxygen in the heart muscle. Springfield, Ill.: Ch. C. Thomas 1971
Rakušan, K., Blahitka, J.: Cardiac output distribution in rats measured by injection of radioactive microspheres via cardiac puncture. Canad. J. Physiol. Pharmacol.52, 230–235 (1974)
Roughton, F. J. W., Scholander, P. F.: Micro gasometric estimation of the blood gases. I. Oxygen. J. biol. Chem.148, 541–550 (1943)
Rushmer, R. P.: Cardiovascular dynamics. Philadelphia: Saunders 1961
Sapirstein, R. P.: Fractionation of the cardiac output of rats with isotopic potassium. Circulat. Res.9, 689–692 (1956)
Sapirstein, L. A.: Regional blood flow by fractional distribution of indicators. Amer. J. Physiol.193, 161–168 (1958)
Snedecor, G. W., Cochran, W. G.: Statistical methods. Ames, Iowa: Iowa State University Press 1967
Thews, G.: Die Sauerstoffdiffusion im Gehirn; ein Beitrag zur Frage der Sauerstoffversorgung der Organe. Pflügers Arch. ges. Physiol.271, 197–226 (1960)
Timiras, P. S.: Comparison of growth and development of rat at high altitude and at sea level. In: The physiological effects of high altitude, W. H. Weihe, ed., pp. 21–30. Oxford: Pergamon Press 1964
Timiras, P. S., Krum, A. A., Pace, N.: Body and organ weights of rats during acclimatization to an altitude of 12470 feet. Amer. J. Physiol.191, 589–604 (1957)
Timiras, P. S., Woolley, D. E.: Functional and morphological development of brain and other organs at high altitude. Fed. Proc.25, 1312–1320 (1966)
Turek, Z., Frans, A., Kreuzer, F.: Hypoxic pulmonary steady-state diffusing capacity for CO and alveolar-arterial O2 pressure differences in growing rats after adaptation to a simulated altitude of 3500 m. Pflügers Arch.335, 1–9 (1972a)
Turek, Z., Ringnalda, B. E. M., Hoofd, L. J. C., Frans, A., Kreuzer, F.: Cardiac output, arterial and mixed-venous O2 saturation, and blood O2 dissociation curve in growing rats adapted to a simulated altitude of 3500 m. Pflügers Arch.335, 10–18 (1972b)
Turek, Z., Grandtner, M., Kreuzer, F.: Cardiac hypertrophy, capillary and muscle fiber density, muscle fiber diameter, capillary radius and diffusion distance in the myocardium of growing rats adapted to a simulated altitude of 3500 m. Pflügers Arch.335, 19–28 (1972c)
Turek, Z., Ringnalda, B. E. M., Grandtner, M., Kreuzer, F.: Myoglobin distribution in the heart of growing rats exposed to a simulated altitude of 3500 m in their youth or born in the low pressure chamber. Pflügers Arch.340, 1–10 (1973a)
Turek, Z., Grandtner, M., Ringnalda, B. E. M., Kreuzer, F.: Hypoxic pulmonary steady-state diffusing capacity for CO and cardiac output in rats born at a simulated altitude of 3500 m. Pflügers Arch.340, 11–18 (1973b)
Turek, Z., Kreuzer, F., Hoofd, L. J. C.: Advantage or disadvantage of a decrease of blood oxygen affinity for tissue oxygen supply at hypoxia. A theoretical study comparing man and rat. Pflügers Arch.342, 185–197 (1973c)
Turek, Z., Kreuzer, F.: Changes in oxygen transport at high altitude, particularly concerning the heart muscle. Krogh Centenary Symposium: Capillary Exchange, Pulmonary Edema and Respiratory Adaptations, Srinagar, Kashmir, October 14–16 (1974)
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Turek, Z., Turek-Maischeider, M., Claessens, R.A. et al. Coronary blood flow in rats native to simulated high altitude and in rats exposed to it later in life. Pflugers Arch. 355, 49–62 (1975). https://doi.org/10.1007/BF00584799
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DOI: https://doi.org/10.1007/BF00584799