Titre
Enhanced acute antihypertensive effect of propranolol in the absence of circulating epinephrine in the rat
Type
article
Institution
Externe
Périodique
Auteur(s)
Burris, J. F.
Auteure/Auteur
Waeber, B.
Auteure/Auteur
Nussberger, J.
Auteure/Auteur
Brunner, H. R.
Auteure/Auteur
Liens vers les personnes
ISSN
0160-2446
Statut éditorial
Publié
Date de publication
1984-08
Volume
6
Numéro
4
Première page
697
Dernière page/numéro d’article
700
Langue
anglais
Notes
Journal Article
Research Support, Non-U.S. Gov't --- Old month value: Jul-Aug
Research Support, Non-U.S. Gov't --- Old month value: Jul-Aug
Résumé
beta-Adrenoceptor blocking agents might reduce blood pressure, in part, by blocking presynaptic beta-adrenoceptors. Absence of circulating epinephrine should then reduce the antihypertensive effect of propranolol. Biadrenalectomized Wistar-Kyoto rats were made hypertensive with methylprednisolone (20 mg/kg s.c. weekly), given for 2 weeks, and supplemented with deoxycorticosterone pivalate (10 mg/kg weekly). Sham-operated controls received the same treatment. Baseline weight, mean intraarterial blood pressure, and heart rate of the groups were the same. After propranolol (5 mg/kg s.c.) was administered to the unanesthetized rats, blood pressure fell within 90 min from 151 +/- 4 by 23 +/- 4 mm Hg (mean +/- SEM) in the adrenalectomized animals and from 153 +/- 4 by only 7 +/- 3 mm Hg in the sham-operated controls (p less than 0.001); heart rate fell by 91 +/- 13 beats/min in the adrenalectomized animals and by 40 +/- 11 beats/min in the controls (p less than 0.01). Propranolol's vehicle had no effect. At the end of the experiment, plasma epinephrine levels were less than 40 pg/ml for adrenalectomized rats, and 420 +/- 60 pg/ml for controls. Norepinephrine levels were approximately equal in the two groups. Since blood pressure fell despite virtual absence of circulating epinephrine, these results suggest that propranolol reduces blood pressure, at least in part, by mechanisms other than presynaptic beta-adrenoceptor blockade.
Sujets
PID Serval
serval:BIB_AF03D354549B
PMID
Date de création
2008-03-05T15:41:03.506Z
Date de création dans IRIS
2025-05-20T22:09:41Z