Chapter One
Role of Local Renin Angiotensin
Systems in Cardiac Damage
Michael Bader
Introduction
The renin angiotensin system (RAS) recently celebrated its 100th anniversary.
In 1898, renin was discovered by Tigerstedt and Bergman in
rabbit kidney (Tigerstedt and Bergman, 1898). Renin turned out to be
the rate limiting enzyme of a proteolytic cascade leading to the formation
of angiotensin (Ang) I and Ang II. In this cascade renin splits the liver-derived
renin substrate, angiotensinogen (AOGEN), in the plasma to
form the decapeptide Ang I (Bader and Ganten, 2000). Ang I is then
metabolized further into the octapeptide Ang II via the endothelium-bound
angiotensin-converting enzyme (ACE). Ang II is one of the most
potent vasopressor substances and releases aldosterone from the adrenal
gland. The effects of the peptide are transmitted by two main G-protein-coupled
receptors, A[T.sub.1] and A[T.sub.2], that were originally ... read full excerpt from Renin Angiotensin System and the Heart ebook
