| Abstract: | The inotropic response of the myocardium to extrasystolic treatment was studied on isolated perfused papillary muscles from rats with postinfarction cardiosclerosis. The development of postinfarction cardiosclerosis was accompanied by a decrease in myocardial excitability. The amplitude of extrasystolic contractions in the remodeled myocardium far surpassed the control. However, the amplitude of postextrasystolic contraction did not surpass that in normal contraction—relaxation cycle. Our results suggest that the ability of the sarcoplasmic reticulum in cardiomyocytes to accumulate Ca2+ is impaired during postinfarction remodeling.__________Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 139, No. 6, pp. 613–616, June, 2005 |
