|
|
|
|
|
Tostes,R.C.; Nigro,D.; Fortes,Z.B.; Carvalho,M.H.C.. |
The cardiovascular protective actions of estrogen are partially mediated by a direct effect on the vessel wall. Estrogen is active both on vascular smooth muscle and endothelial cells where functionally competent estrogen receptors have been identified. Estrogen administration promotes vasodilation in humans and in experimental animals, in part by stimulating prostacyclin and nitric oxide synthesis, as well as by decreasing the production of vasoconstrictor agents such as cyclooxygenase-derived products, reactive oxygen species, angiotensin II, and endothelin-1. In vitro, estrogen exerts a direct inhibitory effect on smooth muscle by activating potassium efflux and by inhibiting calcium influx. In addition, estrogen inhibits vascular smooth muscle cell... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Sex hormones; Estrogen; Vascular smooth muscle; Endothelium nitric oxide; Endothelium-derived hyperpolarizing factor; Angiotensin; Endothelin-1; Calcium channels; Potassium channels. |
Ano: 2003 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2003000900002 |
| |
|
|
Oliveira,Antonio Costa de. |
The discovery of potassium channels on the plasma membrane has helped to elucidate important mechanisms in animal and plant physiology. Plant growth and development associated mechanisms, such as germination, leaf movements, stomatal action, ion uptake in roots, phloem transport and nutrient storage are linked to potassium transport. Studies describing potassium transport regulation by abscisic acid (ABA), Ca++, light and other factors are presented here. Also the types of channels that regulate potassium uptake and efflux in the cell, and the interaction of these channels with external signals, are discussed. |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Ionic channels; Potassium channels. |
Ano: 1995 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84781995000100033 |
| |
|
|
López-Canales,J.S.; Lozano-Cuenca,J.; Muãoz-Islas,E.; Aguilar-Carrasco,J.C.; López-Canales,O.A.; López-Mayorga,R.M.; Castillo-Henkel,E.F.; Valencia-Hernández,I.; Castillo-Henkel,C.. |
Amfepramone (diethylpropion) is an appetite-suppressant drug used for the treatment of overweight and obesity. It has been suggested that the systemic and central activity of amfepramone produces cardiovascular effects such as transient ischemic attacks and primary pulmonary hypertension. However, it is not known whether amfepramone produces immediate vascular effects when applied in vitro to rat aortic rings and, if so, what mechanisms may be involved. We analyzed the effect of amfepramone on phenylephrine-precontracted rat aortic rings with or without endothelium and the influence of inhibitors or blockers on this effect. Amfepramone produced a concentration-dependent vasorelaxation in phenylephrine-precontracted rat aortic rings that was not affected by... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cardiovascular pharmacology; Amfepramone; Obesity; Rat aorta; Nitric oxide; Potassium channels. |
Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2015000600537 |
| |
|
| |
|
|
Cunha,J.F.; Campestrini,F.D.; Calixto,J.B.; Scremin,A.; Paulino,N.. |
We examined some of the mechanisms by which the aspirin metabolite and the naturally occurring metabolite gentisic acid induced relaxation of the guinea pig trachea in vitro. In preparations with or without epithelium and contracted by histamine, gentisic acid caused concentration-dependent and reproducible relaxation, with mean EC50 values of 18 µM and Emax of 100% (N = 10) or 20 µM and Emax of 92% (N = 10), respectively. The relaxation caused by gentisic acid was of slow onset in comparison to that caused by norepinephrine, theophylline or vasoactive intestinal peptide (VIP). The relative rank order of potency was: salbutamol 7.9 > VIP 7.0 > gentisic acid 4.7 > theophylline 3.7. Gentisic acid-induced relaxation was markedly reduced (24 ± 7.0, 43... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Gentisic acid; Potassium channels; Vasoactive intestinal peptide; VIP; Trachea; Smooth muscle. |
Ano: 2001 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2001000300013 |
| |
|
|
López-Canales,J.S.; López-Sanchez,P.; Perez-Alvarez,V.M.; Wens-Flores,I.; Polanco,A.C.; Castillo-Henkel,E.; Castillo-Henkel,C.. |
The relaxant effect of the methyl ester of rosuvastatin was evaluated on aortic rings from male Wistar rats (250-300 g, 6 rats for each experimental group) with and without endothelium precontracted with 1.0 µM phenylephrine. The methyl ester presented a slightly greater potency than rosuvastatin in relaxing aortic rings, with log IC50 values of -6.88 and -6.07 M, respectively. Unlike rosuvastatin, the effect of its methyl ester was endothelium-independent. Pretreatment with 10 µM indomethacin did not inhibit, and pretreatment with 1 mM mevalonate only modestly inhibited the relaxant effect of the methyl ester. Nω-nitro-L-arginine methyl ester (L-NAME, 10 µM), the selective nitric oxide-2 (NO-2) inhibitor 1400 W (10 µM), tetraethylammonium (TEA, 10 mM),... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Rat aorta; Rosuvastatin methyl ester; Endothelium-independent relaxation; Potassium channels; NOS-2. |
Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2011000500009 |
| |
|
|
|