ACE2 and heart failure: Besides Ang II and Ang I, ACE2 can cleave several other substrates including des-Arg9-bradykinin (DABK), apelin-13, and dynorphin A-(1–13; Skidgel and Erdos, 1987; Ferrario et al., 1997; Vickers et al., 2002; Oudit et al., 2003) In addition to its membrane form, ACE2 can be found in a soluble form (sACE2) and increasing sACE2 has been reported in patients with cardiomyopathies and heart failure (Epelman et al., 2008).