Calcium Exchangeable Fraction of Sarcoplasmic Reticulum in Hypertrophic Dog Heart

Publisher Website
Google Scholar
Abstract
Cardiac hypertrophy in weanling beagle dogs was obtained by a loose aortic banding with a 10 mm Dacron-Teflon band, positioned 1 cm distal from the aortic valve. All animals developed left ventricular hypertrophy without signs of heart failure 9 mo. later. Sarcoplasmic reticulum proteins as well as their Ca-exchanging properties were measured in the hypertrophic heart and in those from sham-operated control animals. The Ca exchangeable fraction for the hypertrophic heart was higher than for controls, while sarcoplasmic reticulum proteins obtained from hypertrophic hearts were lower than those obtained from control animals. The increase in the Ca exchangeable fraction probably represents a mechanism of compensation in an early stage of development of the hypertrophic heart whose sarcoplasmic reticulum fraction is not adequately developed.