Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1993-3-10
pubmed:abstractText
We wished to examine whether enhanced depressor baroreflexes contribute to the hypotensive effect of clonidine in rats. Clonidine's hypotensive effect and clonidine's effect on baroreflex gain mean heart rate/mean blood pressure, (delta HR/delta BP) were compared under two conditions: in conscious rats with intact baroreflex control of HR, and in pentobarbital-anesthetized (PA) rats in which baroreflex control of HR is obtunded. Clonidine produced greater hypotension and bradycardia in PA rats than in conscious rats, but this greater hypotension was not associated with enhancement of baroreflex gain. Instead, clonidine-induced hypotension in PA rats was associated with a further decrease in baroreflex gain, whereas hypotension in conscious rats was not associated with any change in baroreflex gain. Selective pharmacologic blockade of sympathetic (i.e., with atenolol treatment) or parasympathetic (i.e., with methyl-atropine treatment) control of HR showed that clonidine decreased baroreflex gain in PA rats through inhibition of sympathetic control of HR. This study suggests that clonidine's hypotensive effect is not associated with enhancement of reflex bradycardic responses in rats.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0160-2446
pubmed:author
pubmed:issnType
Print
pubmed:volume
21
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
264-71
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Hypotensive effect of clonidine is not mediated by enhanced baroreflex gain in rats.
pubmed:affiliation
Department of Pharmacology, University of North Carolina, Chapel Hill 27599-7455.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S.