Opioid binding properties of the purified kappa receptor from human placenta

Journal Article · Sun Jan 01 00:00:00 EST 1989 · Life Sci.; (United States)

DOI:https://doi.org/10.1016/0024-3205(89)90586-9· OSTI ID:6257718

Ahmed, M S; Zhou, D; Cavinato, A G; Maulik, D

A glycoprotein with a molecular weight of 63,000 has been purified, in an active form, from human placental villus tissue membranes. The binding properties of this glycoprotein to opioid alkaloids and peptides indicates that it is the kappa opiate receptor of human placenta. The receptor binds the tritiated ligands etorphine, bremazocine, ethylketocyclazocine and naloxone specifically and reversibly with Kd values of 3.3, 4.4, 5.1 and 7.0nM, respectively. The binding of /sup 3/H-Bremazocine to the purified receptor is inhibited by the following compounds with the corresponding Ki values EKC, 1.3 x 10/sup -8/M; Dynorphin 1-8, 3.03 x 10/sup -7/; U50,488H, 4.48 x 10/sup -9/; U69-593,2.28 x 10/sup -8/, morphine, 4.05 x 10/sup -6/ DADLE, 6.47 x 10/sup -6/ and naloxone, 2.64 x 10/sup -8/. The purified receptor binds 8 nmole of /sup 3/H-Etorphine and 1.7 nmole /sup 3/H-BZC per mg protein. The theoretical binding capacity of a protein of this molecular weight is 15.8. Although the iodinated purified receptor appears by autoradiography as one band on SDS-PAGE, yet homogeneity of the preparation is not claimed.

• Research Organization: Univ. of Missouri, Kansas City (USA)
• OSTI ID: 6257718
• Journal Information: Life Sci.; (United States), Vol. 44:13
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
GLYCOPROTEINS
RECEPTORS
BIOCHEMICAL REACTION KINETICS
CELL MEMBRANES
ELECTROPHORESIS
LIGANDS
MAN
MOLECULAR WEIGHT
PLACENTA
TRACER TECHNIQUES
TRITIUM COMPOUNDS
ANIMALS
CELL CONSTITUENTS
FETAL MEMBRANES
ISOTOPE APPLICATIONS
KINETICS
LABELLED COMPOUNDS
MAMMALS
MEMBRANE PROTEINS
MEMBRANES
ORGANIC COMPOUNDS
PRIMATES
PROTEINS
REACTION KINETICS
VERTEBRATES
550201* - Biochemistry- Tracer Techniques