(Hypertension. 2002;39:e29.)
© 2002 American Heart Association, Inc.
Letters to the Editor |
Cardiovascular Medicine and Gene Therapy Section, INBB National Laboratory, Osilo, Italy, and, Department of Internal Medicine, University of Sassari, Italy
To the Editor:
We read with interest the article "Angiotensinogen and Its Cleaved Derivatives Inhibit Angiogenesis" by Celerier et al.1 At physiological concentrations, angiotensinogen (AGT), des(angiotensin I)angiotensinogen (des[Ang I]-AGT), and reactive center loop cleaved AGT affect endothelial cell (EC) phenotype toward antiangiogenesis. The renin-angiotensin system (RAS) and the kallikrein-kinin system (KKS), regarded as opposing forces in blood pressure control, share instead similarities as modulators of EC biology. Cleavage of kininogen (KNG) by kallikrein leads to formation of des(kinin)-KNG, which, similar to des(Ang I)-AGT, is antiangiogenic.2 Furthermore, angiotensin-converting enzyme (ACE) generates Ang II and degrades kinins, and both of these effects are considered proangiogenic. By extension, attention should be paid to the consequences that antihypertensive treatment, by interfering with RAS and KKS, might have on reparative or tumoral angiogenesis.
Under ACE inhibition (ACEI) or Ang II AT1 receptor blockade, compensatory increase in renin release leads to accelerated AGT cleavage, thereby augmenting angiogenesis inhibitors des(Ang I)AGT and Ang (1-7). Furthermore, proangiogenic Ang II is lacking or displaced from receptor. Consequently, the equilibrium is shifted toward inhibition of vascular growth. How can we reconcile these concepts with the opinion that ACEI promotes neovascularization? One possibility involves the increased availability of angiogenic kinins.3 Accordingly, kinin B2receptor disruption abrogates the healing effect of ACEI in a model of hindlimb ischemia.4 Yet, application of ACEI, ramipril, or AT1-receptor blocker, losartan, in coincidence with ischemic events reportedly leads to delayed and impaired postischemic recovery.5 Because the deleterious effects of ramipril are unaltered under combined kinin B1- and
This article has been cited by other articles:
![]() |
A. H. Berg and P. E. Scherer Adipose Tissue, Inflammation, and Cardiovascular Disease Circ. Res., May 13, 2005; 96(9): 939 - 949. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. C. W. Lau, B. Dhillon, H. Yan, P. E. Szmitko, and S. Verma Adipokines: molecular links between obesity and atheroslcerosis Am J Physiol Heart Circ Physiol, May 1, 2005; 288(5): H2031 - H2041. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. E. Ostrowski, A. A. Reilly, D. N. Collins, and A. I. Ramsingh Progression or Resolution of Coxsackievirus B4-Induced Pancreatitis: a Genomic Analysis J. Virol., August 1, 2004; 78(15): 8229 - 8237. [Abstract] [Full Text] [PDF] |
||||
|
Hypertension Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 2002 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |