Kappa-opioid receptor from human placenta: hydrodynamic characteristics and evidence for its association with a G protein

Journal Article · Fri Jan 01 00:00:00 EST 1988 · Life Sci.; (United States)

DOI:https://doi.org/10.1016/0024-3205(88)90159-2· OSTI ID:6292507

Porthe, G; Frances, B; Verrier, B; Cros, J; Meunier, J C

The kappa nature of opioid binding sites in a brush border membrane (BBM) fraction from human placenta has been confirmed: these sites display considerably higher apparent affinity for the kappa selective ligand U-50488 than they do for the ..mu.. and delta selective ligands enkephalin and enkephalyl-Thr, respectively. Two lines of evidence indicated that the placental kappa opioid receptor is capable of interacting with a guanine nucleotide regulatory (G) protein: (i) equilibrium binding of the angonist /sup 3/H-etorphine in the BBM fraction was clearly inhibited by 5'-guanylylimidodiphosphate (Gpp(NH)p), especially in the presence of Na/sup +/ ions while binding of the antagonist /sup 3/H-diprenorphine was significantly less so and (ii) the sedimentation velocity of the kappa opioid receptor was decreased down to about 10 S when the BBM fraction was prelabeled with radioligand in the presence of Gpp(NH)p prior to its solubilization with digitonin. The G protein that mediates the effect of Gpp(NH)p might be neither G/sub s/ nor G/sub i/ since no adenylate cyclase activity could be demonstrated in the BBM fraction from human placenta.

• Research Organization: Centre National de la Recherche Scientifique, Toulouse (France)
• OSTI ID: 6292507
• Journal Information: Life Sci.; (United States), Vol. 43:6
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
ENDORPHINS
RECEPTORS
PROTEINS
BIOCHEMICAL REACTION KINETICS
CHEMICAL COMPOSITION
CELL MEMBRANES
LIGANDS
MAN
PLACENTA
TRACER TECHNIQUES
TRITIUM COMPOUNDS
ANIMALS
AUTONOMIC NERVOUS SYSTEM AGENTS
CELL CONSTITUENTS
DRUGS
FETAL MEMBRANES
ISOTOPE APPLICATIONS
KINETICS
LABELLED COMPOUNDS
MAMMALS
MEMBRANE PROTEINS
MEMBRANES
NEUROREGULATORS
ORGANIC COMPOUNDS
PRIMATES
REACTION KINETICS
VERTEBRATES
550201* - Biochemistry- Tracer Techniques