Expression of skeletal muscle sarcoplasmic reticulum calcium-ATPase is reduced in rats with postinfarction heart failure
- aDepartment of Medicine, University of California, San Francisco, California, USA, bCardiovascular Research Institute, University of California, San Francisco
- Dr Barry M Massie, Cardiology Section (111C), Veterans Affairs Medical Center, 4150 Clement Street, San Francisco, CA 94121, USA.
- Accepted 24 September 1998
Abstract
OBJECTIVE To determine whether heart failure in rats is associated with altered expression of the skeletal muscle sarcoplasmic reticulum Ca2+-ATPase (SERCA).
METHODS SERCA protein and mRNA were examined in the soleus muscles of eight female rats with heart failure induced by coronary artery ligation, six weeks after the procedure (mean (SEM) left ventricular end diastolic pressure 20.4 (2.2) mm Hg) and in six sham operated controls by western and northern analyses, respectively.
RESULTS SERCA-2a isoform protein was reduced by 16% (112 000 (4000)v 134 000 (2000) arbitrary units, p < 0.001), and SERCA-2a messenger RNA was reduced by 59% (0.24 (0.06) v 0.58 (0.02) arbitrary units, p < 0.001). Although rats with heart failure had smaller muscles (0.54 mg/g v 0.66 mg/g body weight), no difference in locomotor activity was observed.
CONCLUSIONS These results may explain the previously documented abnormalities in calcium handling in skeletal muscle from animals with the same model of congestive heart failure, and could be responsible for the accelerated muscle fatigue characteristic of patients with heart failure.
