We also measured the activities of these enzymes in both subpopulations separately and we found that citrate synthase and MCAD were decreased by heart failure-induced by pressure overload in IFM and SSM (Fig. 5D, E, G and H) whereas aconitase as not altered by hear failure in the isolated mitochondria (Fig. 5F and I). The gene discussed is ACADM; the disease is heart failure.