Impaired vasorelaxant responses to natriuretic peptides in the stroke-prone phenotype of spontaneously hypertensive rats
| Autor: | Detlev Ganten, Speranza Rubattu, Miriam Muscolo, Carmine Vecchione, Francesco Cosentino, Rosaria Russo, Carmine Savoia, Massimo Volpe, Armando Natale, Alessandro F. Mele |
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| Rok vydání: | 1998 |
| Předmět: |
Male
medicine.medical_specialty Endothelium Physiology medicine.drug_class Aorta Thoracic Nerve Tissue Proteins Vasodilation In Vitro Techniques Peptide hormone Rats Inbred WKY Nitroglycerin Atrial natriuretic peptide Rats Inbred SHR Internal medicine medicine.artery Natriuretic Peptide Brain Internal Medicine medicine Natriuretic peptide Animals cardiovascular diseases Cyclic GMP Aorta endothelium natriuretic peptides strokes business.industry Brain natriuretic peptide Rats Cerebrovascular Disorders Phenotype Endocrinology medicine.anatomical_structure Hypertension Cardiology and Cardiovascular Medicine business Atrial Natriuretic Factor Carotid Artery Internal Artery |
| Zdroj: | Journal of Hypertension. 16:151-156 |
| ISSN: | 0263-6352 |
| Popis: | BACKGROUND We have previously shown that a locus on rat chromosome 5, termed STR 2, co-localizes with the genes encoding atrial natriuretic and brain natriuretic peptides, and is closely linked to the development of strokes in rats of a F2 hybrid cohort obtained by crossing stroke-prone spontaneously hypertensive rats and spontaneously hypertensive rats. We also demonstrated that there are significant differences in vascular functioning that are co-segregated with stroke latency of stroke-prone spontaneously hypertensive rats. OBJECTIVE To investigate the vascular responses to natriuretic peptides in the stroke-prone phenotype of spontaneously hypertensive rats. DESIGN AND METHODS In view of the important vasoactive properties of natriuretic peptides, we tested the vascular responses to 10(-11)-10(-9) mol/l atrial natriuretic peptide and to 10(-11)-10(-7) mol/l brain natriuretic peptide in isolated rings of aortas and internal carotid arteries obtained from stroke-prone and stroke-resistant spontaneously hypertensive rats. The 6-week-old rats were exposed for 4 weeks either to their regular diet (n = 15 of both strains) or to the stroke-permissive Japanese-style diet (n = 14 of both strains). A group of 14 normotensive, age-matched and sex-matched Wistar-Kyoto rats was also studied. RESULTS Systolic blood pressures in stroke-prone and stroke-resistant spontaneously hypertensive rats were similar, and were significantly higher than those in Wistar-Kyoto rats. Vascular responses to nitroglycerin, atrial natriuretic peptide, and brain natriuretic peptide in rats of the two hypertensive strains and in Wistar-Kyoto rats fed their regular diet were comparable. In contrast, the vasorelaxant responses to atrial natriuretic peptide in stroke-prone spontaneously hypertensive rats fed Japanese diet were lower both in aortas and in internal carotid arteries than were those in spontaneously hypertensive rats (both P < 0.05 by analysis of variance) and in Wistar-Kyoto rats (both P < 0.05). Similarly, vasorelaxant responses to brain natriuretic peptide were lower both in aortas and in internal carotid arteries of stroke-prone spontaneously hypertensive rats than they were in spontaneously hypertensive rats (both P < 0.05) and in Wistar-Kyoto rats (P < 0.05). The responses to nitroglycerin in the stroke-prone spontaneously hypertensive rats and spontaneously hypertensive rats fed Japanese-style diet were also similar. CONCLUSION The vasorelaxant effects of natriuretic peptides are impaired in stroke-prone spontaneously hypertensive rats. This abnormality could play a role in the pathogenesis of stroke incidence in this hypertensive model. |
| Databáze: | OpenAIRE |
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