American journal of hypertension
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Review Comparative Study
How to explain the differences between renin angiotensin system modulators.
Angiotensin II (Ang II) plays important roles in the development of cardiovascular diseases including hypertension, renal diseases, cardiac hypertrophy, congestive heart failure, and ischemic heart disease. Angiotensin II exerts classic hemodynamic and renal effects, but it is also a local biologically active mediator with direct effects on endothelial and smooth muscle cells. Two subtypes of Ang II receptors, type 1 (AT(1)) and type 2 (AT(2)), have been identified. ⋯ Thus, pharmacologic blockade of the AT(1) receptor and resulting overactivation of AT(2) receptors could impair or delay neovascularization in ischemic tissues in patients receiving chronic treatment with angiotensin receptor blockers. In contrast, increased tissue bradykinin resulting from inhibition of converting enzyme could help to restore functional vascularization in ischemic tissues. These basic concepts deserve a second reading and reevaluation to discuss differences in vascular protection in large clinical trials with different classes of drugs acting on the renin-angiotensin system.