Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1992-12-8
pubmed:abstractText
Various dopamine (DA) agonists including propylnorapomorphine, lisuride, bromocriptine, apomorphine and quinpirole were found to reduce adenylate cyclase activity in rat brown adipose tissue homogenates. These inhibitory effects were antagonized, with a very low stereoselectivity, by DA receptor antagonists with the following rank order of potency: haloperidol > (+)-butaclamol > or = (-)-butaclamol >> clozapine > or = (-)-sulpiride > or = (+)-sulpiride > or = eticlopride, but not by the alpha-2 adrenoceptor antagonists, phenoxybenzamine and yohimbine or the serotonin receptor antagonists, ketanserin and metergoline. The selective D1 agonist, fenoldopam, was completely inactive in modifying the basal enzyme activity. DA as well as various DA agonists (lisuride > propylnorapomorphine > bromocriptine > apomorphine > quinpirole) dose-dependently reduced the stimulation of adenylate cyclase activity induced either by forskolin or by the beta adrenoceptor agonist, (-)-isoproterenol. Similar results were obtained also in dispersed brown adipocytes. We also found that DA and various DA receptor agonists induced a significant decrease of beta adrenoceptor-stimulated glycerol and nonesterified fatty acids release from brown adipocytes. This effect was selectively antagonized by haloperidol and butaclamol. Thus, the receptors present on the BAT membranes appear to be dopaminergic in nature although they differ from the classical D2 receptor for the following: 1) the low affinity for the most selective D2, D3 and D4 receptor agonist and antagonist (quinpirole, sulpiride and clozapine); 2) the absence of stereoselectivity for various DA antagonists (butaclamol and sulpiride); and 3) the lack of detectable mRNA encoding D2 or D3 DA receptors.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0022-3565
pubmed:author
pubmed:issnType
Print
pubmed:volume
263
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
823-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:1359119-Adenylate Cyclase, pubmed-meshheading:1359119-Adipose Tissue, Brown, pubmed-meshheading:1359119-Animals, pubmed-meshheading:1359119-Base Sequence, pubmed-meshheading:1359119-Body Temperature Regulation, pubmed-meshheading:1359119-Cyclic AMP, pubmed-meshheading:1359119-Dopamine Agents, pubmed-meshheading:1359119-Fatty Acids, Nonesterified, pubmed-meshheading:1359119-Forskolin, pubmed-meshheading:1359119-Glycerol, pubmed-meshheading:1359119-Lipolysis, pubmed-meshheading:1359119-Lisuride, pubmed-meshheading:1359119-Male, pubmed-meshheading:1359119-Molecular Sequence Data, pubmed-meshheading:1359119-Polymerase Chain Reaction, pubmed-meshheading:1359119-RNA, Messenger, pubmed-meshheading:1359119-Rats, pubmed-meshheading:1359119-Rats, Sprague-Dawley, pubmed-meshheading:1359119-Receptors, Adrenergic, beta, pubmed-meshheading:1359119-Receptors, Dopamine
pubmed:year
1992
pubmed:articleTitle
Biochemical and functional identification of a novel dopamine receptor subtype in rat brown adipose tissue. Its role in modulating sympathetic stimulation-induced thermogenesis.
pubmed:affiliation
Department of Biomedical Sciences and Biotechnologies, School of Medicine, University of Brescia, Italy.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't