Response of the left ventricular connective tissue to hypoxia
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The collagen content (measured as myocardial concentration of hydroxyproline) and dry weight (expressed as ventricle weight to body weight ratio) were determined in the left ventricle of male Sprague-Dawley rats (200–220 g b.wt.) exposed to a simulated altitude of 7,000 m for 18 h a day for 10 days in a hypobaric chamber. Hypoxia resulted in a significant increase (P<0.001) in the mass of the left ventricle with a concomitant significantly increased collagen concentration (P<0.001). The data indicate that hypoxia effects the synthesis of a significant amount of connective tissue in the left ventricle, which is the ventricle not exposed to pressure load.
These results may be related to clinical, hemodynamic, and pathologic observations showing the left ventricular dysfunction in patients with chronic respiratory insufficiency. Since the amount of collagen in the left ventricle might interfere with ventricular contractile function, it is suggested that the hypoxia in these patients could affect the left ventricular myocardium via a direct action on the connective metabolism.
Key wordsHypoxia Left ventricle Connective metabolism
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- 2.Bergman J, Loxley R (1963) Two improved and simplified methods for the spectrophotometric determination of hydroxyproline. Anal Chem 35:1961–1965Google Scholar
- 5.Chvapil M, Hurych J (1968) Control of collagen biosynthesis. In: Hall DA (ed) Review of connective tissue research. Academic Press, New York, pp 67–196Google Scholar
- 6.Cutilletta AF, Dowell RT, Rudnik M, Arcilla RA, Zak R (1975) Regression of myocardial hypertrophy. I. Experimental model, changes in heart weight, nucleic acids and collagen. J Mol Cell Cardiol 7:767–781Google Scholar
- 10.Genovese A, De Alfieri W, Latte S, Chiariello M, Condorelli M (1982) Regression of myocardial hypertrophy in the rat following removal of acute or chronic hypobaric hypoxia. Eur Heart J [Suppl A] 3:161–164Google Scholar
- 14.Meerson FZ (1974) Development of modern components of the mechanism of cardiac hypertrophy. Circ Res [Suppl II] 35:58–63Google Scholar
- 19.Snedecor GW, Cochran WG (1967) Statistical methods. Iowa City Press, IowaGoogle Scholar
- 20.Vogel JHK (1970) Hypoxia, high altitude and the heart. In: Vogel JHK (ed) Advances in cardiology, vol 5. Karger, Basel.Google Scholar