Linked Life Data

6303047

Source:http://linkedlifedata.com/resource/pubmed/id/6303047

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1983-6-17
pubmed:abstractText
The purpose of this work was to demonstrate the presence of alpha-adrenoceptors in a crude membrane preparation made from rabbit bladder base and urethra. This was achieved by radioligand binding studies, using 3H-dihydro-alpha-ergocryptine (3H-DHE) as the radioligand. The specific binding, i.e. the binding that could be inhibited by 10(-5) M phentolamine, was saturable with 73 fmol 3H-DHE bound per mg membrane protein. Binding was at steady state after 60 min., and reversible. Rate constants for association and dissociation were 3 X 10(7) M-1 min.-1, and 2 X 10(-2) min.-1, respectively. A number of compounds were tested for their abilities to compete with 3H-DHE for the binding sites. The relative affinity of some adrenoceptor agonists was: (-)-adrenaline greater than (-)-noradrenaline much greater than (+/-)-isoprenaline. Stereoselectivity was shown, since (-)-noradrenaline had 42 times higher affinity than (+)-noradrenaline. Adrenoceptor antagonists inhibited 3H-DHE binding in the following order of potency: DHE greater than phentolamine much greater than (+/-)-propranolol. The dissociation constant, KD, for DHE to the binding sites was estimated in three different ways. The constants were derived from saturation, competition, and kinetic studies, and gave KD values of 1.1, 1.4 and 0.7 nM, respectively. The results suggest that alpha-adrenoceptors were labelled by 3H-DHE in the tissue homogenates.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0001-6683
pubmed:author
pubmed:issnType
Print
pubmed:volume
52
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
188-94
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1983
pubmed:articleTitle
Demonstration of alpha-adrenoceptors in the rabbit bladder base and urethra with 3H-dihydroergocryptine ligand binding.
pubmed:publicationType
Journal Article