Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1989-8-18
pubmed:abstractText
Guanfacine (Estulic, Tenex), a centrally acting antihypertensive, was investigated for its effects on the heart using isolated cardiac preparations and in patients for antiarrhythmic properties. The tachycardic effects of sympathetic nerve stimulation in spontaneously beating atria were concentration-dependently suppressed by guanfacine. A 50% inhibition was observed in atria from Syrian hamsters, guinea-pigs and rabbits with 1, 5.4 and 20 nmol/l, respectively. In guinea-pig atria the concentration-response curve of guanfacine was shifted to the right in a parallel manner by rauwolscine (pA2 8.58) but was not displaced by prazosine 1 mumol/l. In rabbit right papillary muscles guanfacine 1 to 10 mumol/l increased force of contraction by 13 to 91%. The positive inotropic effect was antagonized by prazosine 1 mumol/l but was not influenced by cimetidine 1 mumol/l or rauwolscine 1 mumol/l. It is concluded that guanfacine activates cardiac postsynaptic a1- and neuronal presynaptic a2-adrenoceptors with a preference to the latter of about 2 orders of magnitude. Direct membrane stabilizing effects in guinea-pig atria were negligible. In 4 patients with coronary heart disease associated with arrhythmia guanfacine 1 mg per day during 10 days decreased ventricular premature contractions, couplets and abolished appearance of ventricular tachycardias. These preliminary clinical results indicate that guanfacine may reduce cardiac risk factors.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0004-4172
pubmed:author
pubmed:issnType
Print
pubmed:volume
39
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
450-4
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:2665757-Aged, pubmed-meshheading:2665757-Animals, pubmed-meshheading:2665757-Anti-Arrhythmia Agents, pubmed-meshheading:2665757-Antihypertensive Agents, pubmed-meshheading:2665757-Cell Membrane, pubmed-meshheading:2665757-Cricetinae, pubmed-meshheading:2665757-Electric Stimulation, pubmed-meshheading:2665757-Guanfacine, pubmed-meshheading:2665757-Guanidines, pubmed-meshheading:2665757-Guinea Pigs, pubmed-meshheading:2665757-Heart, pubmed-meshheading:2665757-Heart Rate, pubmed-meshheading:2665757-Humans, pubmed-meshheading:2665757-Isometric Contraction, pubmed-meshheading:2665757-Male, pubmed-meshheading:2665757-Mesocricetus, pubmed-meshheading:2665757-Middle Aged, pubmed-meshheading:2665757-Myocardial Contraction, pubmed-meshheading:2665757-Papillary Muscles, pubmed-meshheading:2665757-Phenylacetates, pubmed-meshheading:2665757-Rabbits, pubmed-meshheading:2665757-Refractory Period, Electrophysiological
pubmed:year
1989
pubmed:articleTitle
In vitro cardiac effects and antiarrhythmic properties of guanfacine.
pubmed:affiliation
Preclinical Research, Sandoz Ltd., Basle, Switzerland.
pubmed:publicationType
Journal Article, In Vitro