Endothelin-1-mediated vasoconstriction at rest and during dynamic exercise in healthy humans
| العنوان: | Endothelin-1-mediated vasoconstriction at rest and during dynamic exercise in healthy humans |
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| المؤلفون: | D. Walter Wray, Mikael Sander, Anthony J. Donato, Russell S. Richardson, Steven K. Nishiyama, Peter D. Wagner |
| المصدر: | American Journal of Physiology-Heart and Circulatory Physiology. 293:H2550-H2556 |
| بيانات النشر: | American Physiological Society, 2007. |
| سنة النشر: | 2007 |
| مصطلحات موضوعية: | Adult, Male, medicine.medical_specialty, Time Factors, Endothelium, Physiology, Blood Pressure, Physical exercise, Phenylephrine, Heart Rate, Receptors, Adrenergic, alpha-1, Physiology (medical), Internal medicine, Heart rate, Laser-Doppler Flowmetry, medicine, Humans, Infusions, Intra-Arterial, Vasoconstrictor Agents, Muscle, Skeletal, Exercise, Leg, Endothelin-1, Receptors, Endothelin, business.industry, Endothelin 1, Femoral Artery, Endocrinology, medicine.anatomical_structure, Vasoconstriction, Circulatory system, Female, Adrenergic alpha-1 Receptor Agonists, medicine.symptom, Cardiology and Cardiovascular Medicine, business, Adrenergic alpha-Agonists, Blood Flow Velocity, medicine.drug |
| الوصف: | It is now generally accepted that α-adrenoreceptor-mediated vasoconstriction is attenuated during exercise, but the efficacy of nonadrenergic vasoconstrictor pathways during exercise remains unclear. Thus, in eight young (23 ± 1 yr), healthy volunteers, we contrasted changes in leg blood flow (ultrasound Doppler) before and during intra-arterial infusion of the α1-adrenoreceptor agonist phenylephrine (PE) with that of the nonadrenergic endothelin A (ETA)/ETBreceptor agonist ET-1. Heart rate, arterial blood pressure, common femoral artery diameter, and mean blood velocity were measured at rest and during knee-extensor exercise at 20%, 40%, and 60% of maximal work rate (WRmax). Drug infusion rates were adjusted for blood flow to maintain comparable doses across all subjects and conditions. At rest, PE infusion (8 ng·ml−1·min−1) provoked a rapid and significant decrease in leg blood flow (−51 ± 3%) within 2.5 min. Resting ET-1 infusion (40 pg·ml−1·min−1) significantly decreased leg blood flow within 5 min, reaching a maximal vasoconstriction (−34 ± 3%) after 25–30 min of continuous infusion. Compared with rest, an exercise intensity-dependent attenuation to PE-mediated vasoconstriction was observed (−18 ± 5%, −7 ± 2%, and −1 ± 3% change in leg blood flow at 20%, 40%, and 60% of WRmax, respectively). Vasoconstriction in response to ET-1 was also blunted in an exercise intensity-dependent manner (−13 ± 3%, −7 ± 4%, and 2 ± 3% change in leg blood flow at 20%, 40%, and 60% of WRmax, respectively). These findings support a significant contribution of ET-1 and α-adrenergic receptors in the regulation of skeletal muscle blood flow in the human leg at rest and suggest a similar, intensity-dependent “lysis” of peripheral ET and α-adrenergic vasoconstriction during dynamic exercise. |
| تدمد: | 1522-1539 0363-6135 |
| الوصول الحر: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::0b235ed239b2faebde07be3a86c07a1eTest https://doi.org/10.1152/ajpheart.00867.2007Test |
| رقم الانضمام: | edsair.doi.dedup.....0b235ed239b2faebde07be3a86c07a1e |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 15221539 03636135 |
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