Renin excess after renin inhibition: malefactor or innocent bystander?

New insights into target organ involvement in hypertension

Hypertension and its sequelae are complex processes. Optimization of the care of the hypertensive patient requires not only attention to the regulation of arterial pressure but also attention to blunting the hypertension-related processes that lead to vascular disease. It is clear that the regulation of these processes is much more complex than previously understood. Here several new insights into the pathogenesis of hypertension-related vascular disease have been explored. While this review is not exhaustive, it does serve to point out the varied nature of the biologic processes that must be taken into account and it points to new avenues for the development of therapeutic agents.

Newer Insights into the Biochemical Physiology of the Renin–Angiotensin System: Role of Angiotensin-(1-7), Angiotensin Converting Enzyme 2, and Angiotensin-(1-12)

Knowledge of the mechanisms by which the rennin–angiotensin system contributes to cardiovascular pathology continues to advance at a rapid pace as newer methods and therapies uncover the nature of this complex system and its fundamental role in the regulation of blood pressure and tissue function. The characterization of the biochemical pathways and functions mediated by angiotensin-(1-7) [Ang-(1-7)], angiotensin converting enzyme 2 (ACE2), and the mas receptor has revealed a vasodepressor and antiproliferative axis that within the rennin–angiotensin system opposes the biological actions of angiotensin II (Ang II). In addition, new research expands on this knowledge by demonstrating additional mechanisms for the formation of Ang II and Ang-(1-7) through the existence of an alternate form of the angiotensinogen substrate [angiotensin-(1-12)] which generates Ang II and even Ang-(1-7) through a non-renin dependent action. Altogether, this research paves the way for a better understanding of the intracellular mechanisms involved in the synthesis of angiotensin peptides and its consequences in terms of cell function in both physiology and pathology.