Korean J Intern Med.  2013 Mar;28(2):197-205. 10.3904/kjim.2013.28.2.197.

Additional antihypertensive effect of magnesium supplementation with an angiotensin II receptor blocker in hypomagnesemic rats

• Jin K
• Kim TH
• Kim YH
• Kim YW

• KMID: 1501775
• DOI: http://doi.org/10.3904/kjim.2013.28.2.197

Abstract

BACKGROUND/AIMS
Magnesium (Mg) is an essential element for vascular function and blood pressure regulation. Several studies have demonstrated that Mg concentration is inversely associated with blood pressure, and that Mg supplementation attenuates hypertension. The purpose of this study was to evaluate the effect of dietary Mg supplementation on the blood pressure effects of an angiotensin II receptor blocker (ARB) in hypomagnesemic rats.
METHODS
Fifty male Sprague-Dawley rats were randomly divided into Mg-deficient (n = 30), normal diet plus Mg (n = 10), and control groups (n = 10). Mg-free, high-Mg, and normal-Mg diets were respectively fed to the rats. After 14 weeks, 10 of the 30 Mg-deficient rats were treated with Mg, 10 Mg-deficient rats received an ARB, and 10 Mg-deficient rats received an ARB plus Mg for 4 weeks.
RESULTS
Systolic blood pressure was significantly higher in the Mg-deficient rats than in the control rats at week 14. Hypomagnesemic rats exhibited decreased systolic blood pressure after treatment with Mg, and systolic blood pressure showed a greater decrease after ARB treatment. Treatment with the ARB/Mg combination resulted in the greatest decrease in systolic blood pressure. Mg deficiency did not affect the serum angiotensin II level, but did increase the serum aldosterone concentration. Concomitant Mg/ARB supplementation significantly decreased the elevated serum aldosterone level in hypomagnesemic rats. Kidney tissues of the hypomagnesemic rats revealed mild to moderate inflammatory infiltrates. Mg and/or ARB treatment did not reverse the inflammatory reaction in the kidneys of hypomagnesemic rats.
CONCLUSIONS
Concurrent dietary Mg supplementation can enhance ARB-induced blood pressure reduction in rats with hypomagnesemic hypertension.

Keyword

Magnesium; Hypertension; Angiotensin receptor antagonists

MeSH Terms

Aldosterone/blood
Angiotensin II/blood
Angiotensin II Type 1 Receptor Blockers/*pharmacology
Animals
Antihypertensive Agents/*pharmacology
Biological Markers/blood
Blood Pressure/*drug effects
*Dietary Supplements
Disease Models, Animal
Hypertension/blood/*drug therapy/pathology/physiopathology
Kidney/drug effects/pathology
Magnesium/blood/*pharmacology
Magnesium Deficiency/blood/*drug therapy/pathology/physiopathology
Male
Rats
Rats, Sprague-Dawley
Systole
Time Factors
Angiotensin II Type 1 Receptor Blockers
Antihypertensive Agents
Biological Markers
Angiotensin II
Aldosterone
Magnesium