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Absence of coronary or aortic atherosclerosis in rats having dietary lipid modified vulnerability to cardiac arrhythmias

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      Abstract

      Laboratory studies have shown that saturated fats in the diet increase vulnerability to ventricular fibrillation and other cardiac arrhythmias while polyunsaturates, especially the n − 3 fatty acids of fish oils, are antiarrhythmic. Similarly, dietary saturated fat has been implicated in the development of coronary atherosclerosis while polyunsaturated fatty acids are reported to provide protection. In the present study, dietary fat supplements known to influence arrhythmic vulnerability after long term feeding in the rat were tested for their propensity to induce or prevent changes in the aorta or coronary vasculature. It was found that dietary supplementation for 15 months with saturated fat (from sheep fat) or n − 6 (sunflower seed oil) or n − 3 (fish oil) polyunsaturated fatty acids made no difference to the development of vascular changes in coronary arteries or aorta of the rat despite some significant differences in plasma triglyceride and cholesterol levels. The vascular lesions observed were minimal even in non-supplemented age-matched reference animals. They consisted of focal intimal thickening and slight mucopolysaccharide accumulation with no evidence of progression to fibrotic lesions or calcium accumulation and there were no fatty deposits observed. It is concluded that significant atherosclerosis-induced chronic myocardial ischaemia in no way contributes to dietary lipid modulation of arrhythmic vulnerability in the rat.

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      References

        • Buxton A.E.
        Sudden cardiac death.
        Ann. Intern. Med. 1986; 104: 716
        • McLennan P.L.
        • Abeywardena M.Y.
        • Chamock J.S.
        Dietary fish oil prevents ventricular fibrillation following coronary artery occlusion and reperfusion.
        Am. Heart J. 1988; 116: 709
        • McLennan P.L.
        • Abeywardena M.Y.
        • Charnock J.S.
        The influence of age and dietary fat in an animal model of sudden cardiac death.
        Aust. N.Z. J. Med. 1989; 19: 1
        • McLennan P.L.
        • Abeywardena M.Y.
        • Chamock J.S.
        Influence of dietary lipids on arrhythmiss and infarction after coronary artery ligation in rats.
        Can. J. Physiol. Pharmacol. 1985; 63: 1411
        • Davies M.J.
        • Thomas A.C.
        Plaque fissuring — the cause of acute myocardial infarction, sudden ischaemic death and crescendo angina.
        Br. Heart J. 1985; 53: 363
        • Goodnight S.H.
        • Harris W.R.
        • Connor W.E.
        • Illingworth D.R.
        Polyunsaturated fatty acids, hyperhpidaemia and thrombosis.
        Arteriosclerosis. 1980; 2: 87
        • Keefe D.L.
        • Schwartz J.
        • Somberg J.C.
        The substrate and the trigger: the role of myocardial vulnerability in sudden cardiac death.
        Am. Heart J. 1987; 113: 218
        • Hartroft W.S.
        • Thomas W.A.
        Induction of experimental arterosclerosis in various animals.
        in: Sandier M. Bourne G.H. Atherosclerosis and Its Origin. Academic Press, New York1963: 439
        • Nakamura H.
        • Izumiyama N.
        • Nakamura K.
        • Ohtsubo K.
        Age-associated ultrastructural changes in the aortic intima of rats with diet-induced hypercholesterolemia.
        Atherosclerosis. 1989; 79: 101
        • Chamock J.S.
        • McLennan P.L.
        • Abeywardena M.Y.
        • Russell G.R.
        Altered levels of Math Eq fatty acids in rat heart and storage fat following variable dietary intake of linoleic acid.
        Ann. Nutr. Metab. 1985; 29: 279
        • Charnock J.S.
        • Abeywardena M.Y.
        • McLennan P.L.
        Comparative changes in the fatty-acid composition of rat cardiac phospholipids after long-term feeding of sunflower seed oil- or tuna fish oil-supplemented diets.
        Ann. Nutr. Metab. 1986; 30: 393
        • Warner R.G.
        • Brever Jr., L.H.
        Nutrition requirements of the laboratory rat.
        in: Nutrition requirements of laboratory animals. 3rd edn. Natl. Acad. Sci.10. 1972: 56
        • McIntosh G.H.
        • McLennan P.L.
        • Lawson C.A.
        • Bulman F.H.
        • Charnock J.S.
        The influence of dietary fats on plasma lipids, blood pressure and coagulation indices in the rat.
        Atherosclerosis. 1985; 55: 125
        • Holman R.L.
        • McGill H.C.
        • Strong J.P.
        • Geer J.C.
        Technics for studying atherosclerotic lesions.
        Lab. Invest. 1985; 7: 42
        • Kaneda T.
        • Nakajima A.
        • Fujimoto K.
        • Kobayashi T.
        • Kiriyama S.
        • Ebihara K.
        • Innami T.
        • Tsuji E.
        • Kinumaki T.
        • Shimma H.
        • Yoneyama S.
        Quantitative analysis of cholesterol in foods by gas-liquid chromatography.
        J. Nutr. Sci. Vitaminol. 1980; 26: 497
        • Wexler B.C.
        Spontaneous coronary arteriosclerosis in repeatedly bred male and female rats.
        Circ. Res. 1964; 14: 32
        • Wissler R.W.
        Principles of the pathogenesis of atherosclerosis.
        in: 3rd edn. Heart Disease. Vol. 2. Saunders, New York1980: 1221
        • Wexler B.C.
        Spontaneous arteriosclerosis in old, male, virgin Sprague-Dawley rats.
        Arterosclerosis. 1979; 34: 277
        • Abeywardena M.Y.
        • McLennan P.L.
        • Charnock J.S.
        Long-term saturated fat supplementation inthe rat causes an increase in Math Eq ratio of platelet and vessel wall compared to n − 3 and n − 6 dietary fatty acids.
        Atherosclerosis. 1987; 66: 181