Fig. 5. mTOR inhibition alleviates cardiac dysfunction and blunted β-adrenergic response in lamp2^e2/e2.

A. Representative end-diastolic and end-systolic images of ventricles from echocardiography. B-D. In vivo parameters of cardiac pump function via HFE (N=11 for all groups). Both ejection fraction (EF%) and fractional area contractility (FAC%) were reduced in lamp2^e2/e2 (LM), and were partially rescued in lamp2^e2/e2 ; xu015^+/− (LMT). Fractional shortening (FS%) at the long axis (LAX), but not short axis (SAX), was rescued. E-G. Ex vivo indices of the response to isoproterenol (N=15 for the wild-type, 16 for lamp2^e2/e2, and 11 for lamp2^e2/e2 ; xu015^+/−). The ISO-induced increase of EDV (ΔEDV) and EF (ΔEF) were blunted in LM, but rescued in LMT group. By contrast, the ISO-induced increase in ESV (ΔESV) was not affected. (Mean ± SEM in the ex vivo ISO response experiment). * P < 0.05, LM to WT, # P <0.05, LMT to LM group (rescue).