Involvement of endogenous ouabain-like compound in the cardiac hypertrophic process in vivo.

Abstract The Na + /K + -ATPase inhibitor ouabain has been shown to trigger hypertrophic growth of cultured cardiomyocytes; however, the significance of endogenous ouabain-like compound (OLC) in the hypertrophic process in vivo is unknown. Here we characterized the involvement of OLC in left ventricular (LV) hypertrophy induced by norepinephrine (NE) and angiotensin II (Ang II) infusions in rats. Administration of NE (300 μg/kg/h) via subcutanously implanted osmotic minipumps for 72 h resulted in a significant increase in left ventricular weight to body weight (LVW/BW) ratio ( P P P P P P