This Article Full Text (PDF) References Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Stein, F. L. P. Articles by Baisch, A. L. M. Search for Related Content PubMed PubMed Citation Articles by Stein, F. L. P. Articles by Baisch, A. L. M. Social Bookmarking                         What's this?

Vascular Responses to Extractable Fractions of Ilex paraguariensis in Rats Fed Standard and High-Cholesterol Diets

Programa de Pós-Graduação em Ciências Fisiológicas-Fisiologia Animal Comparada

Bruno Schmidt

Departamento de Ciências Fisiológicas

Eliana Badiale Furlong, PhD

Departamento de Química and in the Programa de Pós-Graduação em Engenharia de Alimentos

Leonor A. Souza Soares, PhD

Departamento de Química and in the Programa de Pós-Graduação em Engenharia de Alimentos

Maria Cristina Flores Soares, PhD

Departamento de Ciências Fisiológicas, and in the Programa de Pós-Graduação em Enfermagem

Marta R. Cezar Vaz, PhD

Departamento de Enfermagem and in the Programa de Pós-Graduação em Enfermagem

Ana L. Muccillo Baisch, PhD

Departamento de Ciências Fisiológicas and in the Programa de Pós-Graduação em Ciências Fisiológicas Fisiologia Animal Comparada, and in the Programa de Pós-Graduação em Enfermagem, abaisch{at}octopus.furg.br

The authors investigated the vasorelaxant properties of the aqueous (Aq-EF) and acid n-butanolic (acn-BuOH) extractable fractions from Ilex paraguariensis leaves. Perfusion pressure was evaluated using isolated and perfused mesenteric arterial beds (MABs) from rats fed hypercholesterolemic and standard diets. Extract-induced vasorelaxation in the presence and absence of various inhibitors was examined following precontraction of the MABs with methoxamine (30 µM) solution. In hypercholesterolemic-diet rats, relaxation in intact MABs was significantly decreased with ac-n-BuOH-EF bolus (300, 600, 900 µg) in comparison to those in standard-diet rats. After the endothelium was stripped from the MABs, the vascular responses to ac-n-BuOH-EF and 900 µg bolus of Aq-EF were significantly changed. Treatment of the MABs with an inhibitor of nitric oxide synthase, N^G-nitro-L-arginine methylester hydrochloride (L-NAME, 10 mM), did not change either ac-n-BuOH-EF- or Aq-EF-induced vasodilation except for the 900 g bolus of Aq-EF. The guanilate cyclase inhibitor methylene blue (100 µM) did not affect vasodilation for either fraction in the MABs from the hypercholesterolemic-diet rats. The chronic oral administration of I. paraguariensis extract in hypercholesterolemic-diet rats resulted in a significant reduction in serum levels of cholesterol and triglycerides. These results suggest that I. paraguariensis ac-n-BuOH-EF and Aq-EF induce vasodilation in standard-diet rats in a dose-dependent manner and that the hypercholesterolemic diet substantially reduced the effect of ac-n-BuOH-EF on precontracted MABs.

Key Words: mesenteric arterial bed • flavonoids • experimental hypercholesterolemia • endothelium • Ilex paraguariensis • basic science and nursing

Biological Research For Nursing, Vol. 7, No. 2, 146-156 (2005)
DOI: 10.1177/1099800405280521


CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?