Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1991-1-24
pubmed:abstractText
The regional binding of the opiate receptor ligand diprenorphine has been examined in rat brain both in vivo and in vitro. The time course of total label in specific brain regions was followed up to 2 h after intravenous bolus injection of [3H]diprenorphine, with or without a pulse chase of unlabelled diprenorphine at 30 min. In addition, total label was measured 30 min after injection of labelled diprenorphine at nontracer concentrations over a range of specific activities. Total data sets for each region were fitted simultaneously to a compartmental model to give estimates of maximal binding capacity (Bmax), the second-order apparent association rate constant, and the first-order dissociation rate constant of the receptor-ligand complex. The model incorporated the use of a reference region with low specific binding (cerebellum). The binding of diprenorphine to rat brain homogenates was measured in vitro under equilibrium conditions at 37 degrees C, pH 7.4, in the presence and absence of naloxone, to give corresponding regional estimates of Bmax and the half-saturation constant Kd. The results showed a close correlation between in vitro and in vivo regional estimates of Bmax over a wide range. There were no significant interregional differences either in Kd in vitro or in the Kd derived from the in vivo analysis, although in vitro and in vivo estimates differed by an order of magnitude. This work was carried out as part of a validation study with a view to the application of the compartmental model to data obtained in vivo in humans using positron emission tomography, when successive studies over a range of specific activities are not feasible.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0271-678X
pubmed:author
pubmed:issnType
Print
pubmed:volume
11
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Compartmental analysis of diprenorphine binding to opiate receptors in the rat in vivo and its comparison with equilibrium data in vitro.
pubmed:affiliation
MRC Cyclotron Unit, Hammersmith Hospital, London, England.
pubmed:publicationType
Journal Article, Comparative Study