Simultaneous release of endothelium-derived relaxing and contracting factors induced by noradrenaline in normotensive rats.
1. Noradrenaline produced a biphasic response in indomethacin (10(-5) M)-treated aorta isolated from normotensive rats. 2. The relaxation phase is enhanced by previous treatment of the animals with estrogen. 3. Blockade of the relaxant effect elicited by supramaximal concentration of noradrenaline was observed when 10(-5) M of methylene blue was present in the bathing fluid for 15 min. 4. Noradrenaline caused a simultaneous release of endothelium-derived relaxing and contracting factors in aorta from normotensive rats.
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Department of Pharmacology, University of São Paulo, Brazil.
Fortes
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ZB
Scivotetto
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Carvalho
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MH
D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects; D016232:Endothelins; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism*; D005260:Female; D066298:In Vitro Techniques; D007213:Indomethacin / Q000494:pharmacology; D008297:Male; D008751:Methylene Blue / Q000494:pharmacology; D009119:Muscle Contraction / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects; D009569:Nitric Oxide / Q000378:metabolism*; D009638:Norepinephrine / Q000494:pharmacology*; D010455:Peptides / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains
D016232:Endothelins; D010455:Peptides; D009569:Nitric Oxide; D008751:Methylene Blue; D009638:Norepinephrine; D007213:Indomethacin