Kidney Res Clin Pract.  2016 Mar;35(1):15-21. 10.1016/j.krcp.2015.12.003.

Direct vascular actions of quercetin in aorta from renal hypertensive rats

• Choi S
• Ryu KH
• Park SH
• Jun JY
• Shin BC
• Chung JH
• Yeum CH

• KMID: 2161497
• DOI: http://doi.org/10.1016/j.krcp.2015.12.003

Abstract

BACKGROUND
Chronic treatment with the dietary flavonoid quercetin is known to lower blood pressure and restore endothelial dysfunction in animal models of hypertension. This study investigated the direct effects of quercetin on vascular response in chronic 2-kidney, 1-clip (2K1C) renal hypertensive rats. The effects of antioxidant vitamin ascorbic acid on the vasoreactivity were also examined.
METHODS
2K1C renal hypertension was induced by clipping the left renal artery; age-matched rats that received sham treatment served as controls. Thoracic aortae were mounted in tissue baths for the measurement of isometric tension.
RESULTS
Relaxant responses to acetylcholine were significantly attenuated in 2K1C rats in comparison with sham rats. Quercetin or ascorbic acid augmented acetylcholine-induced relaxation in 2K1C rats, whereas no significant differences were noted in sham rats. The relaxation response to sodium nitroprusside was comparable between 2K1C and sham rats, and sodium nitroprusside-induced relaxation was not altered by quercetin or ascorbic acid in either group. The contractile response to phenylephrine was significantly enhanced in 2K1C rats compared with sham rats. Phenylephrine-induced contraction was inhibited by pretreatment with quercetin or ascorbic acid in 2K1C rats, whereas neither chemical affected responses in sham rats. N(w)-nitro-L-arginine methyl ester markedly augmented the contractile response to phenylephrine in sham rats, whereas no significant differences were observed in 2K1C rats. Quercetin or ascorbic acid did not affect phenylephrine-induced contraction in the presence of N(w)-nitro-L-arginine methyl ester in either 2K1C or sham rats.
CONCLUSION
Acute exposure to quercetin appears to improve endothelium-dependent relaxation and inhibit the contractile response, similar to the effect of ascorbic acid in 2K1C hypertension. These results partially explain the vascular beneficial effects of quercetin in renal hypertension.

Keyword

Antioxidant; Quercetin; Renal hypertension

MeSH Terms

Acetylcholine
Animals
Aorta*
Aorta, Thoracic
Ascorbic Acid
Baths
Blood Pressure
Hypertension
Hypertension, Renal
Models, Animal
Nitroprusside
Phenylephrine
Placebos
Quercetin*
Rats*
Relaxation
Renal Artery
Sodium
Vitamins
Acetylcholine
Ascorbic Acid
Nitroprusside
Phenylephrine
Placebos
Quercetin
Sodium
Vitamins