Endothelium-derived relaxing factor alters calcium fluxes in rabbit aorta: a cyclic guanosine monophosphate-mediated effect.
AUTOR(ES)
Collins, P
RESUMO
1. Measurement of tension and 45Ca influx and efflux were used to study the effects of endothelium-derived relaxing factor (EDRF), sodium nitroprusside and 8-bromo-cyclic guanosine monophosphate (GMP) on contractile responses and calcium movements in aortic ring preparations of the rabbit. 2. EDRF activity, induced by stimulating endothelium-containing rings with acetylcholine, was associated with relaxation of noradrenaline-constricted rings and with a marked reduction of noradrenaline-stimulated increase in calcium influx. Sodium nitroprusside and 8-bromo-cyclic GMP had a similar effect in de-endothelialized preparations. 3. EDRF also inhibited noradrenaline-stimulated calcium efflux. Sodium nitroprusside and 8-bromo-cyclic GMP had a similar effect in de-endothelialized preparations, both in the presence and absence of extracellular calcium. 4. The vascular smooth muscle relaxant effect of EDRF and of nitrovasodilators may be effected by a cyclic GMP-mediated reduction of cytosolic calcium, through both inhibition of calcium influx and reduction of intracellular calcium release.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1182988Documentos Relacionados
- Endothelium-derived relaxing factor inhibits the formation of inositol trisphosphate by rabbit aorta.
- Identification of arginine as a precursor of endothelium-derived relaxing factor.
- Endothelium-derived relaxing factor and nitroprusside compared in noradrenaline- and K+-contracted rabbit and rat aortae.
- Endothelium-derived relaxing factor reduces platelet adhesion to bovine endothelial cells.
- Mechanism of action of some inhibitors of endothelium-derived relaxing factor.
