Format

Send to

Choose Destination
Vasc Health Risk Manag. 2009;5(1):73-8. Epub 2009 Apr 8.

Arterial stiffness in insulin resistance: the role of nitric oxide and angiotensin II receptors.

Author information

1
St George Clinical School, University of New South Wales, Kogarah, NSW, Australia.

Abstract

The insulin resistance syndrome (INSR) is associated with increased cardiovascular risk, and affects up to 25% of the Australian population aged >20 years. Increased arterial stiffness has been proposed as a common pathway by which INSR leads to increased cardiovascular risk. We have reviewed the role of nitric oxide (NO) and angiotensin II receptors in the modulation of arterial stiffness in the setting of insulin resistance. There is emerging evidence that early stages of INSR may be characterized by increased basal nitric oxide activity and increased activity of non-NO vasodilators such as endothelial derived hyperpolarization factor (EDHF) which is manifest by reduced arterial stiffness. Depletion of NO or ineffectiveness of NO mediated vasodilator mechanisms associated with the progression of INSR to type 2 diabetes may result in increased arterial stiffness, which predicts the development of cardiovascular disease. Thus in the early stages of INSR, increased NO and EDHF activity may represent compensatory mechanisms to early vascular damage. The renin-angiotensin system is activated in diseased vascular beds, with up regulation of the two known angiotensin II receptors: the angiotensin II type 1 receptor (AT1R) and the angiotensin II type 2 receptor (AT2R). Increased AT1R mediated activity in the vasculature is central to the development of increased arterial stiffness and is enhanced in INSR states. AT2R activity is increased in early in INSR and may contribute to the apparent increase in basal NO activity. AT1R blockade may therefore be valuable treatment for early INSR as antagonism of AT1 receptors would allow angiotensin II to act unopposed at AT2 receptors.

KEYWORDS:

AT1 receptor; AT2 receptor; arterial stiffness; diabetes; insulin resistance; nitric oxide; obesity

PMID:
19436651
PMCID:
PMC2672440
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Dove Medical Press Icon for PubMed Central
Loading ...
Support Center