Long- and short-term effects of androgens in human umbilical artery smooth muscle.
Clin Exp Pharmacol Physiol
; 40(3): 181-9, 2013 Mar.
Article
em En
| MEDLINE
| ID: mdl-23278339
ABSTRACT
The aim of the present study was to determine the effects of androgens in the regulation of human umbilical artery (HUA) contractility. The short-term effects of testosterone on the tone of the HUA were investigated, as were the long-term effects of dihydrotestosterone (DHT) on the expression of some proteins involved in the contractile process. Endothelium-denuded HUA were treated for 24 h with DHT (2 µmol/L) or the vehicle control (ethanol) to analyse the genomic effects of androgens. Twenty-four hour treatment of HUA with DHT increased the mRNA expression of the ß(1)-subunit of the large-conductance Ca(2+)-activated (BK(Ca)) channel and decreased expression of the α-subunit of L-type calcium channels. In organ bath studies, testosterone (1-100 µmol/L) produced similar relaxant responses in DHT- and vehicle-treated HUA rings precontracted with 5-HT, histamine and KCl. However, the relaxation response obtained by the combined application of testosterone (100 µmol/L) and nifedipine (10 µmol/L) was significantly greater in DHT- compared with vehicle-treated HUA. The results indicate that the rapid vasorelaxant effects of testosterone that are dependent on both BK(Ca) and voltage-sensitive potassium (K(V)) channel activity in control arteries become dependent solely on K(V) channel activity in DHT-treated HUA. Thus, the present study reveals the importance of the investigation of both the short- and long-term effects of androgens in human arteries.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Di-Hidrotestosterona
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Artérias Umbilicais
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Vasodilatação
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Androgênios
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Contração Muscular
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Músculo Liso Vascular
Limite:
Female
/
Humans
Idioma:
En
Ano de publicação:
2013
Tipo de documento:
Article