| Effect of phenoxybenzamine on cardiovascular and plasma catecholamine responses to clonidine. | |
| | |
MedLine Citation:
|
PMID: 6822028 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
To determine whether the alpha-adrenergic antagonist phenoxybenzamine would alter cardiovascular or plasma catecholamine response to the alpha-adrenergic agonist clonidine, six patients with pheochromocytomas and eight with labile hypertension were studied. Clonidine, 0.3 mg, was given with and without 48 hr pretreatment with 30 mg/day phenoxybenzamine. The response to 10 mg diazepam was also observed in seven of the subjects who had labile hypertension. In the hypertensive patients, clonidine alone induced a fall in supine blood pressure from 137 +/- 21/91 +/- 14 to 109 +/- 18/76 +/- 17 mm Hg and, with phenoxybenzamine, clonidine reduced blood pressure from 141 +/- 22/89 +/- 10 to 107 +/- 21/72 +/- 11 mm Hg. Plasma norepinephrine fell from 179 +/- 60 to 107 +/- 79 pg/ml without phenoxybenzamine and from 229 +/- 159 to 95 +/- 46 pg/ml with phenoxybenzamine in hypertensive subjects. Responses with phenoxybenzamine did not differ from those without phenoxybenzamine and diazepam induced no cardiovascular or plasma catecholamine changes. Clonidine did not lower plasma catecholamines in patients with a pheochromocytoma in the presence or in the absence of phenoxybenzamine. Blood pressure tended to decline after clonidine in pheochromocytoma patients not taking phenoxybenzamine, but it was not reduced by clonidine when these patients were taking phenoxybenzamine. Phenoxybenzamine does not inhibit reduction in blood pressure and plasma catecholamines induced by clonidine in patients with essential hypertension or interfere with the clonidine suppression test in patients with pheochromocytomas. |
| | |
Authors:
|
A Zweifler; M Gross; J Sisson |
Related Documents
:
|
2887648 - Effects of the alpha 2-adrenergic agonist clonidine and its antagonist idazoxan on the ... 4043678 - Studies of the antidiarrheal action of clonidine. effects on motility and intestinal ab... 2513858 - Comparison of the effects of extradural clonidine with those of morphine on postoperati... 8872298 - Effective antihypertensive therapy: blood pressure control with moxonidine. 19206798 - Wideband absorbance tympanometry using pressure sweeps: system development and results ... 12069188 - Tissue damage of non-heart-beating donor lungs after long-term preservation: evaluation... |
Publication Detail:
|
Type: Journal Article; Research Support, U.S. Gov't, P.H.S. |
Journal Detail:
|
Title: Clinical pharmacology and therapeutics Volume: 33 ISSN: 0009-9236 ISO Abbreviation: Clin. Pharmacol. Ther. Publication Date: 1983 Feb |
Date Detail:
|
Created Date: 1983-03-17 Completed Date: 1983-03-17 Revised Date: 2007-11-14 |
Medline Journal Info:
|
Nlm Unique ID: 0372741 Medline TA: Clin Pharmacol Ther Country: UNITED STATES |
Other Details:
|
Languages: eng Pagination: 156-62 Citation Subset: AIM; IM |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Blood Pressure
/
drug effects Clonidine / pharmacology* Drug Interactions Epinephrine / blood Humans Hypertension / complications, drug therapy Norepinephrine / blood Phenoxybenzamine / pharmacology* Pheochromocytoma / complications |
| Grant Support | |
ID/Acronym/Agency:
|
5-M01-RR-42/RR/NCRR NIH HHS; HL 21893/HL/NHLBI NIH HHS |
| Chemical | |
Reg. No./Substance:
|
4205-90-7/Clonidine; 51-41-2/Norepinephrine; 51-43-4/Epinephrine; 59-96-1/Phenoxybenzamine |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Bretylium kinetics in renal insufficiency.
Next Document: Total and free propranolol levels in sensitive and resistant patients.