REN and Stroke: The renin–angiotensin–aldosterone system (RAAS), also referred to as the angiotensin (Ang)-converting enzyme/Ang II/Ang type 1 receptor axis, is altered following cerebrovascular injuries such as stroke and BCAS-induced hypoperfusion and is known to induce injury in various organs, affecting cardiac function, renal function, as well as cognitive function (32, 82, 83).