Campo DC | Valor | Idioma |
dc.contributor.author | Lahlou, Saad | - |
dc.contributor.author | Correia Junior, Carlos Antônio de Barros | - |
dc.contributor.author | Santos, Márcio Vasconcelos dos | - |
dc.contributor.author | David, Jorge Mauricio | - |
dc.contributor.author | David, Juceni Pereira de Lima | - |
dc.contributor.author | Duarte, Glória Pinto | - |
dc.contributor.author | Magalhães, Pedro Jorge Caldas | - |
dc.creator | Lahlou, Saad | - |
dc.creator | Correia Junior, Carlos Antônio de Barros | - |
dc.creator | Santos, Márcio Vasconcelos dos | - |
dc.creator | David, Jorge Mauricio | - |
dc.creator | David, Juceni Pereira de Lima | - |
dc.creator | Duarte, Glória Pinto | - |
dc.creator | Magalhães, Pedro Jorge Caldas | - |
dc.date.accessioned | 2012-07-03T15:02:01Z | - |
dc.date.available | 2012-07-03T15:02:01Z | - |
dc.date.issued | 2007 | - |
dc.identifier.issn | 1537-1891 | - |
dc.identifier.uri | http://www.repositorio.ufba.br/ri/handle/ri/6298 | - |
dc.description | RESTRITO | pt_BR |
dc.description.abstract | Cardiovascular effects of Labd-8 (17)-en-15-oic acid (Labd-8), a labdenic diterpene isolated from methanolic extract of Moldenhawera nutans
were investigated in normotensive rats. Additionally, this study examined the role of autonomic nervous system in the mediation of these
cardiovascular effects. In pentobarbital-anesthetized rats, bolus intravenous (i.v.) injection of Labd-8 (1–10 mg/kg) induced dose-dependent
hypotensive and tachycardiac responses. After cervical bivagotomy, hypotensive responses to Labd-8 were significantly enhanced whereas the
tachycardia was completely abolished. In conscious rats, Labd-8 (1–10 mg/kg, i.v.) also decreased blood pressure and increased heart rate in a
dose-dependent manner. Pretreatment with methylatropine (1 mg/kg, i.v.) or propranolol (2 mg/kg, i.v.) significantly reduced the tachycardia
evoked by Labd-8 without affecting the hypotension. Blockade of ganglionic neurotransmission with hexamethonium (30 mg/kg, i.v.) reduced and
abolished the hypotensive and tachycardic effects of Labd-8, respectively. However, hypotensive effects of Labd-8 were not reduced by
pretreatment with Nw-nitro-L-arginine methyl ester (L-NAME; 20 mg/kg, i.v.), a nitric oxide synthase inhibitor. In rat endothelium-containing
aorta preparations, Labd-8 (1–1000 μg/ml) induced a concentration-dependent reduction of potassium (60 mM)-induced contraction [IC50
(geometric mean ±95% confidence interval)=313.6 (191.4–513.8) μg/ml], an effect that remained unaffected [IC50=440.8 (225.1–863.3) μg/ml]
by removal of vascular endothelium. These results show that i.v. treatment with Labd-8-induced dose-dependent hypotensive and tachycardiac
effects in both conscious and anesthetized rats. The tachycardia is mediated reflexly through inhibition of vagal and activation of sympathetic
drive to the heart. The hypotension is mainly due to withdrawal of sympathetic tone to the vasculature and also partly to an active vascular
relaxation. Released nitric oxide from vascular endothelial cells is not involved in the mediation of Labd-8-induced hypotension. | pt_BR |
dc.language.iso | en | pt_BR |
dc.publisher | Vascular Pharmacology | pt_BR |
dc.source | http://dx.doi.org/10.1016/j.vph.2006.06.010 | pt_BR |
dc.subject | Autonomic nervous system | pt_BR |
dc.subject | Cardiovascular effects | pt_BR |
dc.subject | Isolated thoracic aorta | pt_BR |
dc.subject | Labd-8(17)-en-15-oic acid | pt_BR |
dc.subject | Leguminosae | pt_BR |
dc.subject | Moldenhawera nutans | pt_BR |
dc.subject | Rat | pt_BR |
dc.title | Mechanisms underlying the cardiovascular effects of a labdenic diterpene isolated from Moldenhawera nutans in normotensive rats | pt_BR |
dc.title.alternative | Vascular Pharmacology | pt_BR |
dc.type | Artigo de Periódico | pt_BR |
dc.identifier.number | v.46, n.1 | pt_BR |
Aparece nas coleções: | Artigo Publicado em Periódico (Faculdade de Medicina)
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