Soluble low affinity adenosine A/sub 2/ binding site from human placenta: reconstitution and characteristics
The authors have developed a vesicle reconstitution technique that allows for rapid vacuum filtration assay, and have characterized the soluble A/sub 2/ site from placental membranes. The overall yield of reconstituted binding is 60%. Competition analysis of membranes and reconstituted vesicles yields identical agonist potency orders and affinities: N-ethylcarboxamidoadenosine (NECA) (Kd-330 nM)>2-chloroadenosine (Kd=1.7 ..mu..M) > L-phenylisopropyladenosine (Kd > 1 mM). Equilibrium binding to membranes and reconstituted vesicles of (/sup 3/H)-NECA, an adenosine agonist, was not reduced by guanine nulceotides. HPLC gel permeation chromatography of extracts from membranes preincubated with 5 mM MgCl/sub 2/ and 100 ..mu..M NECA revealed a peak of binding with kD of 0.07. Extracts prepared with either an antagonist or NECA and 100 ..mu..M guanylyl 5'-imidodiphosphate revealed a peak of binding with a kD of 0.09. These data suggest that the adenosine A/sub 2/ receptor retains its binding properties upon reconstitution and may couple to a guanine nucleotide regulatory protein.
- Research Organization:
- Univ. Hospitals, Ann Arbor, MI
- OSTI ID:
- 6126878
- Report Number(s):
- CONF-870644-; TRN: 87-033989
- Journal Information:
- Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States), Vol. 46:6; Conference: 78. annual meeting of the American Society of Biological Chemists conference, Philadelphia, PA, USA, 7 Jun 1987
- Country of Publication:
- United States
- Language:
- English
Similar Records
Adenosine receptor modulation of seizure susceptibility in rats
( sup 3 H)CGS 21680, a selective A2 adenosine receptor agonist directly labels A2 receptors in rat brain
Related Subjects
ADENOSINE
RECEPTORS
BIOCHEMICAL REACTION KINETICS
AFFINITY
CELL MEMBRANES
LIQUID COLUMN CHROMATOGRAPHY
MAN
PLACENTA
TRACER TECHNIQUES
TRITIUM COMPOUNDS
ANIMALS
CELL CONSTITUENTS
CHROMATOGRAPHY
FETAL MEMBRANES
ISOTOPE APPLICATIONS
KINETICS
LABELLED COMPOUNDS
MAMMALS
MEMBRANE PROTEINS
MEMBRANES
NUCLEOSIDES
NUCLEOTIDES
ORGANIC COMPOUNDS
PRIMATES
PROTEINS
REACTION KINETICS
RIBOSIDES
SEPARATION PROCESSES
VERTEBRATES
550201* - Biochemistry- Tracer Techniques