Journal article
Beta-2 adrenergic blockade evaluated with epinephrine after placebo, atenolol, and nadolol
Clinical pharmacology and therapeutics, Vol.37(1), pp.2-6
01/1985
DOI: 10.1038/clpt.1985.2
PMID: 2856902
Abstract
Vascular β2-adrenergic blocking effects of the water-soluble drugs atenolol (β1-selective) and nadolol (nonselective) were evaluated. Twenty-four healthy young men were studied in three dosing groups (eight subjects per group) before and after 1 wk on placebo, atenolol (50 mg twice a day), or nadolol (40 mg twice a day). Maximal treadmill exercise heart rates were reduced to a similar degree by atenolol (−48 ± 3 bpm) and nadolol (−48 ± 4 bpm) but were not affected by placebo. Trough blood levels were 226 ± 9 ng/ml for atenolol and 43 ± 9 ng/ml for nadolol. Calf blood flow was measured with a plethysmograph and calf vascular resistance was calculated from blood pressure and flow. β2-Adrenergic blockade was determined at rest with epinephrine infused intravenously in graded doses from 0.001 to 0.032 µg/kg/min. Mean arterial pressure and calf vascular resistance rose markedly after nadolol but not after atenolol or placebo. Marked bradycardia developed after nadolol, probably by baroreceptor stimulation. Thus at an equivalent, substantial degree of β1-adrenergic blockade, nadolol blocks vascular β2-adrenergic receptors and atenolol does not. Measurement of the peripheral vascular response to epinephrine infusion is an effective means of assessing the impact of β-adrenergic blockers on vascular β2-adrenergic receptors.
Details
- Title: Subtitle
- Beta-2 adrenergic blockade evaluated with epinephrine after placebo, atenolol, and nadolol
- Creators
- William R Hiatt - University of Colorado HealthEugene E Wolfel - University of Colorado HealthSandra Stoll - University of Colorado HealthAlan S Nies - University of Colorado HealthGary O Zerbe - University of Colorado HealthH L Brammell - University of Colorado HealthLawrence D Horwitz - University of Colorado Health
- Resource Type
- Journal article
- Publication Details
- Clinical pharmacology and therapeutics, Vol.37(1), pp.2-6
- DOI
- 10.1038/clpt.1985.2
- PMID
- 2856902
- ISSN
- 0009-9236
- eISSN
- 1532-6535
- Language
- English
- Date published
- 01/1985
- Academic Unit
- Cardiovascular Medicine; Internal Medicine
- Record Identifier
- 9984656592402771
Metrics
12 Record Views