Noradrenaline-induced contraction of mice aorta is enhanced in schistosomiasis.
Vascul Pharmacol
; 46(2): 122-8, 2007 Feb.
Article
em En
| MEDLINE
| ID: mdl-17049461
Schistosomiasis, an intravascular parasitic disease caused by Schistosoma mansoni, is related to alterations of murine vascular reactivity in the mesenteric bed, characterized by an impairment of the l-arginine/NO pathway and an increased potency of 5-hydroxytryptamine. The current study was performed to test the hypothesis that a similar alteration of reactivity also occurs in the aorta and to identify the mechanism behind such an increase. We found that aorta from mice infected with male S. mansoni exhibited an enhanced contraction in response to noradrenaline and 100 mM KCl. The inhibition of nitric oxide synthase increased aortic maximal contraction in response to noradrenaline in both groups, but the effect was less pronounced in infected mice than in control mice. Endothelium-dependent relaxation induced by acetylcholine was also smaller in infected mice compared to control mice, while endothelial-independent relaxation induced by sodium nitroprusside and forskolin was similar in both groups. The inhibition of voltage-dependent L-type Ca(2+) channels reduced the maximal contraction in response to noradrenaline more effectively in infected than in control mice. Conversely the inhibition of K(ATP) channels had a smaller effect in the infected group. As a conclusion, our data indicate that schistosomiasis also alters murine vascular reactivity outside the mesenteric bed, due to a partial impairment of NO signaling, a reduced contribution of K(ATP) channels and an increased Ca(2+) influx through L-type Ca(2+) channels.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Aorta Torácica
/
Vasoconstritores
/
Vasodilatação
/
Esquistossomose mansoni
/
Norepinefrina
Limite:
Animals
Idioma:
En
Revista:
Vascul Pharmacol
Assunto da revista:
ANGIOLOGIA
/
FARMACOLOGIA
Ano de publicação:
2007
Tipo de documento:
Article
País de afiliação:
Brasil
País de publicação:
Estados Unidos