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Non-invasive Assessment of Microvascular and Endothelial Function
05:41

Non-invasive Assessment of Microvascular and Endothelial Function

Published on: January 29, 2013

Insulin sensitivity and endothelial function in hypertension: a comparison of temocapril and candesartan

Hirofumi Tomiyama1, Kohki Motobe, Gulnisa Zaydun

  • 1Second Department of Internal Medicine, Tokyo Medical University, Tokyo, Japan. tomiyama@tokyo-med.ac.jp

American Journal of Hypertension
|March 9, 2005
PubMed

Insights

Angiotensin-converting enzyme inhibitors (ACEi) improved endothelial function more than angiotensin II receptor blockers (ARB), but both treatments had similar effects on insulin sensitivity in hypertensive patients.

Area of Science:

  • Cardiovascular Pharmacology
  • Metabolic Disorders
  • Hypertension Management

Background:

  • Emerging evidence suggests angiotensin-converting enzyme inhibitors (ACEi) may offer superior endothelial function (END) benefits compared to angiotensin II receptor blockers (ARB).
  • The differential impact of ACEi and ARB on insulin sensitivity (IS) in hypertensive individuals remains unclear.
  • This study investigates the comparative effects of ACEi and ARB on END and IS in patients with hypertension.

Purpose of the Study:

  • To compare the efficacy of ACEi versus ARB in modulating endothelial function.
  • To assess the impact of ACEi and ARB on insulin sensitivity in hypertensive patients.
  • To explore potential biochemical pathways influencing these effects.

Main Methods:

  • A crossover study involving 23 hypertensive patients receiving ACEi or ARB for 8-week intervals.
  • Endothelial function assessed via forearm blood flow response to reactive hyperemia.
  • Insulin sensitivity evaluated using an insulin tolerance test; plasma levels of bradykinin (BK), NOx, tumor necrosis factor-alpha (TNF-alpha), and adiponectin (Adi) were measured.

Main Results:

  • ACEi treatment resulted in significantly higher endothelial function, bradykinin (BK), and nitric oxide (NOx) levels compared to ARB.
  • Insulin sensitivity and adiponectin (Adi) levels were comparable between ACEi and ARB treatments.
  • Tumor necrosis factor-alpha (TNF-alpha) levels were lower following ARB treatment than with ACEi.

Conclusions:

  • ACEi and ARB demonstrate similar effects on insulin sensitivity, despite ACEi's more pronounced impact on endothelial function.
  • The bradykinin-nitric oxide (BK-NO) pathway may partly explain the enhanced endothelial effects of ACEi.
  • Under physiological conditions, endothelial function may not be a primary determinant of insulin sensitivity.
Abstract

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