Linked Life Data

1657295

Source:http://linkedlifedata.com/resource/pubmed/id/1657295

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1991-12-20
pubmed:abstractText
1-Isoproterenol has equal affinity for beta 1- and beta 2-adrenoceptors and is a full agonist at both subtypes. However, when infused in vivo into the rat brain, it has been shown to induce a preferential reduction of central beta 2-adrenoceptors. To investigate this phenomenon further, in the present study rats were infused centrally with higher doses of 1-isoproterenol (15 or 45 micrograms/h). Furthermore, isoproterenol was infused into rats lesioned neonatally with 6-hydroxydopamine (6-OHDA). Subtypes of beta-adrenoceptors were measured by quantitative autoradiography of the binding of [125I]iodopindolol ([125I]IPIN). In sham lesioned rats, infusions of isoproterenol at both doses caused comparable reductions in the density of [125I]IPIN binding sites in many brain regions. The binding to beta 2-adrenoceptors was decreased in a larger number of brain areas than the binding to beta 1-adrenoceptors and the magnitude of the reduction was greater for beta 2- than for beta 1-adrenoceptors. However, isoproterenol at these doses did produce greater effects on the beta 1-subtype than those found previously with a lower dose. Treatment with 6-OHDA induced significant increases in the binding of [125I]IPIN to both beta 1- and beta 2-adrenoceptors in cerebral cortical and hippocampal areas, indicating that endogenous norepinephrine may regulate both subtypes in these regions. Even in the 6-OHDA-lesioned rats, the binding of [125I]IPIN to beta 2-adrenoceptors was reduced to a greater extent that the binding to beta 1-adrenoceptors. Thus, these studies demonstrate that the non-selective beta-adrenergic agonist isoproterenol induces a preferential regulation of beta 2-adrenoceptors, even at relatively high doses and in norepinephrine-depleted animals.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0006-8993
pubmed:author
pubmed:issnType
Print
pubmed:day
26
pubmed:volume
555
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
141-8
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Central administration of 1-isoproterenol in vivo induces a preferential regulation of beta 2-adrenoceptors in the central nervous system of the rat.
pubmed:affiliation
Dept. of Psychiatry, University of Pennsylvania, Philadelphia.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.