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Updated: Aug 4, 2026
06:39
Ultrasound Based Assessment of Coronary Artery Flow and Coronary Flow Reserve Using the Pressure Overload Model in Mice
Published on: April 13, 2015
AT1 receptors: coronary flow and flow reserve
1Alton Ochsner Medical Foundation, New Orleans, Louisiana 70121, USA.
American Journal of Hypertension
|March 11, 2000
Summary
Angiotensin II receptor blockers improved coronary flow reserve in hypertensive rats more than ACE inhibitors. Combination therapy nearly normalized reserve, suggesting benefits for hypertensive heart disease.
Area of Science:
- Cardiovascular Medicine
- Pharmacology
- Hypertension Research
Background:
- Angiotensin II elevates arterial pressure and worsens hypertensive heart disease via the angiotensin-type 1 receptor.
- Coronary hemodynamic alterations, such as reduced coronary blood flow and flow reserve, contribute to cardiovascular risk in hypertension.
- Hypertensive heart disease involves impaired coronary circulation, increasing cardiovascular risk.
Purpose of the Study:
- To compare the effects of angiotensin II receptor blockers (ARBs) and angiotensin converting enzyme inhibitors (ACEIs) on coronary hemodynamics in spontaneously hypertensive rats.
- To evaluate the impact of combination ARB and ACEI therapy on coronary flow reserve in the context of hypertensive heart disease.
Main Methods:
- Treatment of spontaneously hypertensive rats for 3 months with an ARB, an ACEI, or a combination of both in equidepressor doses.
- Measurement of coronary flow reserve, defined as the difference between basal coronary blood flow and maximal flow during dipyridamole-induced vasodilation.
Main Results:
- ARBs increased coronary flow reserve more effectively than ACEIs in spontaneously hypertensive rats.
- Combination therapy with ARBs and ACEIs almost restored coronary flow reserve to levels observed in normotensive Wistar Kyoto rats.
Conclusions:
- Angiotensin II receptor blockers may offer an advantage over angiotensin converting enzyme inhibitors in improving coronary hemodynamics in hypertensive conditions.
- Combination therapy with ARBs and ACEIs shows potential for restoring coronary flow reserve in patients with hypertension and hypertensive heart disease.
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