High potassium diet augments endothelium-dependent relaxations in the Dahl rat
Autor: | Leopolde Raij, P M Vanhoutte, T F Lüscher |
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Rok vydání: | 1988 |
Předmět: |
Male
Nitroprusside medicine.medical_specialty Endothelium Potassium chemistry.chemical_element Nitric Oxide Nitric oxide chemistry.chemical_compound Biological Factors Norepinephrine Internal medicine Internal Medicine medicine Animals Chemistry Adenosine Acetylcholine Dietary Potassium Diet Rats Vasodilation Endocrinology medicine.anatomical_structure Blood pressure Blood Vessels Sodium nitroprusside Endothelium Vascular medicine.drug |
Zdroj: | Hypertension (Dallas, Tex. : 1979). 12(6) |
ISSN: | 0194-911X |
Popis: | Endothelium-dependent relaxations are reduced in hypertensive rats. High dietary potassium supplementation reduces the incidence of strokes in Dahl rats independently of blood pressure, thereby suggesting a direct protective effect of the diet. Endothelium-dependent relaxations and aortic vascular architecture were studied in Dahl salt-sensitive rats fed 8% NaCl, 0.1% NaCl, or 8% NaCl plus 3.6% potassium citrate for 8 weeks. Rats fed 8% NaCl or 8% NaCl plus 3.6% potassium citrate became hypertensive, while those fed 0.1% NaCl did not. Aortic rings with and without endothelium were suspended in organ chambers filled with physiological salt solution (37 degrees C) and aerated with 95% O2, 5% CO2. In rings contracted with norepinephrine, acetylcholine and adenosine 5'-diphosphate caused endothelium-dependent relaxations that were significantly reduced in rats fed 8% NaCl as compared with those fed 0.1% NaCl. Potassium supplementation (8% NaCl/3.6% potassium citrate) significantly enhanced relaxations to acetylcholine in salt-sensitive rats, while those to adenosine 5'-diphosphate and thrombin were either minimally affected or unchanged. Relaxations to sodium nitroprusside were similar in rats with or without potassium supplementation. Hypertension significantly increased aortic medial and intimal thickness. Dietary potassium had no significant effect on the vascular architecture. These results suggest that high potassium diet enhances endothelium-dependent relaxations in Dahl rats at least in part independently of changes in blood pressure. Thus, potassium may be important for its protective effect against stroke and renal damage in this animal model of hypertension. |
Databáze: | OpenAIRE |
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