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Title: Cardiovascular alterations at different stages of hypertension development during ethanol consumption: Time-course of vascular and autonomic changes

The aim of the present work was to establish a time-course correlation between vascular and autonomic changes that contribute to the development of hypertension during ethanol ingestion in rats. For this, male Wistar rats were subjected to the intake of increasing ethanol concentrations in their drinking water during four weeks. Ethanol effects were investigated at the end of each week. Mild hypertension was already observed at the first week of treatment, and a progressive blood pressure increase was observed along the evaluation period. Increased pressor response to phenylephrine was observed from first to fourth week. α{sub 1}-adrenoceptor protein in the mesenteric bed was enhanced at the first week, whereas β{sub 2}-adrenoceptor protein in the aorta was reduced after the second week. In the third week, ethanol intake facilitated the depressor response to sodium nitroprusside, whereas in the fourth week it reduced nitrate content in aorta and increased it plasma. The bradycardic component of the baroreflex was impaired, whereas baroreflex tachycardia was enhanced at the third and fourth weeks. AT{sub 1A} receptor and C-type natriuretic peptide (CNP) mRNAs in the nucleus tractus solitarius were increased at the fourth week. These findings suggest that increased vascular responsiveness to vasoconstrictor agents is possiblymore » a link factor in the development and maintenance of the progressive hypertension induced by ethanol consumption. Additionally, baroreflex changes are possibly mediated by alterations in angiotensinergic mechanisms and CNP content within the brainstem, which contribute to maintaining the hypertensive state in later phases of ethanol ingestion. Facilitated vascular responsiveness to nitric oxide seems to counteract ethanol-induced hypertension. - Highlights: • Mild hypertension was observed during the entire period of ethanol ingestion. • Ethanol facilitated vascular reactivity to vasoactive agents. • Changes in baroreflex activity contribute to ethanol-evoked hypertension. • Plasma and aortic nitrate content was affected by ethanol consumption. • Ethanol changed AT{sub 1A} receptor and CNP in the nucleus tractus solitaries.« less
Authors:
 [1] ;  [2] ;  [3] ; ;  [2] ;  [3] ; ;  [2] ;  [3]
  1. Department of Natural Active Principles and Toxicology, School of Pharmaceutical Sciences, Univ. Estadual Paulista—UNESP (Brazil)
  2. Department of Physiology, School of Medicine of Ribeirao Preto, University of Sao Paulo (Brazil)
  3. Department of Pharmacology, School of Medicine of Ribeirao Preto, University of Sao Paulo (Brazil)
Publication Date:
OSTI Identifier:
22439871
Resource Type:
Journal Article
Resource Relation:
Journal Name: Toxicology and Applied Pharmacology; Journal Volume: 280; Journal Issue: 2; Other Information: Copyright (c) 2014 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; AORTA; BLOOD PRESSURE; CONCENTRATION RATIO; DRINKING WATER; ETHANOL; HYPERTENSION; INGESTION; MESSENGER-RNA; NITRATES; NITRIC OXIDE; PEPTIDES; RATS; RECEPTORS; SODIUM