Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1990-3-22
pubmed:abstractText
The binding of [3H]Tyr-D-Ala-Gly-(N-Me)Phe-Gly-ol ([3H]DAGO) and [3H]Tyr-D-Thr-Gly-Phe-Leu-Thr ([3H]DTLET), selective agonists for mu- and delta-opioid binding sites, respectively, has been investigated using different rat brain tissue preparations and buffer systems. The results were compared with the binding of the ligands to crude membrane fractions in Tris-HCl, the most commonly used preparation for binding studies. In both rat brain membranes and intact cells, Krebs-HEPES induced a decrease in the affinities of [3H]DAGO and [3H]DTLET, but little modification was observed when 20-microns tissue slices were used, whatever the brain area studied. The dissociation rate of [3H]DTLET was clearly dependent on the tissue preparation used, because the koff value of this ligand in Krebs-HEPES was 2.5-fold higher in membrane fractions than that measured in intact cells. The kinetic dissociation constant of [3H]DTLET in membrane fractions in Krebs-HEPES was 6.5-fold greater than that measured in Tris-HCl. In intact cells, the koff value for [3H]DTLET was lower than that found in membrane fractions in Krebs-HEPES and similar to that observed in membrane preparations in Tris-HCl supplemented with 30 mM NaCl. These data suggest (a) that the koff constant of [3H]DTLET was regulated by the ionic environment of the delta-opioid receptor, which is clearly dependent on the preservation of cellular structure, and (b) that opioid receptors could exist under different states that are regulated, in part, by the intracellular Na+ concentration.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Buffers, http://linkedlifedata.com/resource/pubmed/chemical/Enkephalin, Ala(2)-MePhe(4)-Gly(5)-, http://linkedlifedata.com/resource/pubmed/chemical/Enkephalins, http://linkedlifedata.com/resource/pubmed/chemical/HEPES, http://linkedlifedata.com/resource/pubmed/chemical/Isotonic Solutions, http://linkedlifedata.com/resource/pubmed/chemical/Krebs-Ringer solution, http://linkedlifedata.com/resource/pubmed/chemical/Oligopeptides, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Opioid, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Opioid, delta, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Opioid, mu, http://linkedlifedata.com/resource/pubmed/chemical/Tromethamine, http://linkedlifedata.com/resource/pubmed/chemical/deltakephalin
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0022-3042
pubmed:author
pubmed:issnType
Print
pubmed:volume
54
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
992-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Affinity states of rat brain opioid receptors in different tissue preparations.
pubmed:affiliation
Département de Chimie Organique, U. 266 INSERM and UA 498 CNRS, UER des Sciences Pharmaceutiques et Biologiques, Paris, France.
pubmed:publicationType
Journal Article, Comparative Study