Superoxide dismutase restores endothelium-dependent arteriolar dilatation during acute infusion of nicotine
| Autor: | William G. Mayhan, Glenda M. Sharpe |
|---|---|
| Rok vydání: | 1998 |
| Předmět: |
Male
Nicotine medicine.medical_specialty Physiology Administration Topical Vasodilation Muscle Smooth Vascular Microcirculation Superoxide dismutase Nitroglycerin chemistry.chemical_compound Arteriole Cheek pouch Cricetinae Physiology (medical) Internal medicine medicine.artery medicine Animals Infusions Intravenous Analysis of Variance biology Superoxide Dismutase Chemistry Endothelium-derived relaxing factor Mouth Mucosa Acetylcholine Adenosine Diphosphate Arterioles Cheek Endocrinology Anesthesia cardiovascular system biology.protein Vascular Resistance Endothelium Vascular medicine.drug |
| Zdroj: | Journal of Applied Physiology. 85:1292-1298 |
| ISSN: | 1522-1601 8750-7587 |
| DOI: | 10.1152/jappl.1998.85.4.1292 |
| Popis: | We previously showed [ Am. J. Physiol. 272 ( Heart Circ. Physiol. 41): H2337–H2342, 1997] that nicotine impairs endothelium-dependent arteriolar dilatation. However, mechanisms that accounted for the effect of nicotine on endothelium-dependent vasodilatation were not examined. Thus the goal of this study was to examine the role of oxygen radicals in nicotine-induced impairment of arteriolar reactivity. We measured diameter of cheek pouch resistance arterioles (∼50 μm diameter) in response to endothelium-dependent (ACh and ADP) and -independent (nitroglycerin) agonists before and after infusion of vehicle or nicotine in the absence or presence of superoxide dismutase. ACh, ADP, and nitroglycerin produced dose-related dilatation of cheek pouch arterioles before infusion of vehicle or nicotine. Infusion of vehicle, in the absence or presence of superoxide dismutase (150 U/ml), did not alter endothelium-dependent or -independent arteriolar dilatation. In contrast, infusion of nicotine (2 μg ⋅ kg−1⋅ min−1) impaired endothelium-dependent, but not -independent, arteriolar dilatation. In addition, the effect of nicotine on endothelium-dependent vasodilatation was reversed by topical application of superoxide dismutase. We suggest that nicotine impairs endothelium-dependent arteriolar dilatation via an increase in the synthesis/release of oxygen-derived free radicals. |
| Databáze: | OpenAIRE |
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