5). The effect of ACE2 which has been more extensively investigated is the regulation of the RAAS system, where ACE2 counter-balances ACE, limiting the potent vasoconstrictive effect of angiotensin II (Ang-II). The first evidence that ACE2 was involved in RAAS control came from the transgenic knockout mouse model (ACE2–/–), which was characterized by severe reduction of cardiac contractility and thinn