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U-46619-induced potentiation of noradrenergic constriction in the human saphenous vein: antagonism by thromboxane receptor blockade
- Source :
- Cardiovascular research. 52(3)
- Publication Year :
- 2001
-
Abstract
- Objective: We investigated the potentiating effect of U-46619, a synthetic analogue of thromboxane A2 (TXA2), on the adrenergic responses in human saphenous vein. Methods: Saphenous vein rings were obtained from 35 patients undergoing coronary artery bypass surgery. The rings were suspended in organ bath chambers for isometric recording of tension. Results: U-46619 (10−10–3×10−7 mol/l) produced concentration-dependent and endothelium-independent contractile responses. U-46619 (10−10 mol/l) potentiated the contractions elicited by electrical stimulation and potassium chloride, and produced leftward shifts of the concentration–response curve for noradrenaline. The TXA2 receptor antagonist SQ-30741 (10−8 mol/l) prevented the potentiation evoked by U-46619. The dihydropyridine calcium antagonist nifedipine (10−6 mol/l) did not affect the potentiation of electrical stimulation and noradrenaline induced by U-46619, but abolished the potentiation of U-46619 on KCl-induced contractions. Conclusions: U-46619 facilitates sympathetic neurotransmission and potentiates constrictor effects of noradrenaline in human saphenous veins through stimulation of TXA2 receptors. These effects are independent of calcium entry through dihydropyridine calcium channels.
- Subjects :
- Male
medicine.medical_specialty
Dihydropyridines
Nifedipine
Physiology
medicine.drug_class
Thromboxane
Receptors, Thromboxane
Adrenergic
In Vitro Techniques
Potassium Chloride
Thromboxane receptor
Thromboxane A2
chemistry.chemical_compound
Norepinephrine
Physiology (medical)
Internal medicine
medicine
Humans
Vasoconstrictor Agents
Saphenous Vein
Aged
Voltage-dependent calcium channel
Dose-Response Relationship, Drug
Chemistry
Calcium channel
Dihydropyridine
Drug Synergism
Middle Aged
Receptor antagonist
Calcium Channel Blockers
Electric Stimulation
Stimulation, Chemical
Endocrinology
15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid
Female
Endothelium, Vascular
Cardiology and Cardiovascular Medicine
medicine.drug
Subjects
Details
- ISSN :
- 00086363
- Volume :
- 52
- Issue :
- 3
- Database :
- OpenAIRE
- Journal :
- Cardiovascular research
- Accession number :
- edsair.doi.dedup.....284a7f3f008235c7776ee046e1aab3bb