Disparate Effect of Antioxidant Supplements on the Basal Tone and Vascular Remodeling of the Aorta in Hypertensive Rats.
J Vasc Res
; 57(5): 261-275, 2020.
Article
in En
| MEDLINE
| ID: mdl-32554967
ABSTRACT
BACKGROUND:
Oxidative stress plays an essential role in the vascular tone in hypertension; however, the mechanisms remain unclear.AIM:
This study aimed to determine the antioxidant effect of tempol and vitamin C (Vit-C) on the basal tone and vascular remodeling of the aorta in nitric oxide (NO) deficiency-induced hypertensive rats.METHOD:
Male Sprague-Dawley rats were induced to hypertension by Nω-nitro-L-arginine methyl ester (L-NAME). Animals were randomized as follows vehicle (Control CR), CR-tempol, CR-Vit-C, L-NAME, L-NAME-tempol, and L-NAME-Vit-C. After 6 weeks of treatment, the basal aortic tone was evaluated by sodium nitroprusside (SNP) and calcium-free medium. Endothelial function, NO, reduced-to-oxidized glutathione (GSH/GSSG) ratio, resting membrane potential (mP), and vascular remodeling were also measured.RESULTS:
L-NAME rats showed an increased basal tone that was blunted by both SNP (-547 ± 69; n = 7 vs. CR -7.5 ± 6.7 mg; n = 7; p < 0.001) and calcium-free medium. Tempol or Vit-C did not reverse hypertension, and the high basal tone was decreased only with tempol. In L-NAME rats, only tempol partially improved endothelial function, GSH-to-GSSG ratio, mP values, and vascular remodeling.CONCLUSIONS:
Tempol decreased calcium-dependent basal aortic tone and improved vascular homeostasis in L-NAME rats. Vit-C did not lead to a similar effect, suggesting that alterations in the superoxide dismutase pathway may play a role in the basal aortic tone.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Aorta, Thoracic
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Ascorbic Acid
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Vasoconstriction
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Oxidative Stress
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Dietary Supplements
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Cyclic N-Oxides
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Vascular Remodeling
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Hypertension
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Antioxidants
Limits:
Animals
Language:
En
Journal:
J Vasc Res
Journal subject:
ANGIOLOGIA
Year:
2020
Document type:
Article
Affiliation country: