Identification of leukotriene D4 specific binding sites in the membrane preparation isolated from guinea pig lung

Journal Article · Sat Dec 01 00:00:00 EST 1984 · Prostaglandins; (United States)

DOI:https://doi.org/10.1016/0090-6980(84)90036-4· OSTI ID:5655782

Mong, S; Wu, H L; Clark, M A; Stadel, J M; Gleason, J G; Crooke, S T

A radioligand binding assay has been established to study leukotriene specific binding sites in the guinea pig and rabbit tissues. Using high specific activity (/sup 3/H)-leukotriene D4 (( /sup 3/H)-LTD4), in the presence or absence of unlabeled LTD4, the diastereoisomer of LTD4 (5R,6S-LTD4), leukotriene E4 (LTE4) and the end-organ antagonist, FPL 55712, the authors have identified specific binding sites for (/sup 3/H)-LTD4 in the crude membrane fraction isolated from guinea pig lung. The time required for (/sup 3/H)-LTD4 binding to reach equilibrium was approximately 20 to 25 min at 37 degrees C in the presence of 10 mM Tris-HCl buffer (pH 7.5) containing 150 mM NaCl. The binding of (/sup 3/H)-LTD4 to the specific sites was saturable, reversible and stereospecific. The maximal number of binding sites (Bmax), derived from Scatchard analysis, was approximately 320 +/- 200 fmol per mg of crude membrane protein. The dissociation constants, derived from kinetic and saturation analyses, were 9.7 nM and 5 +/- 4 nM, respectively. The specific binding sites could not be detected in the crude membrane fraction prepared from guinea pig ileum, brain and liver, or rabbit lung, trachea, ileum and uterus. In radioligand competition experiments, LTD4, FPL 55712 and 5R,6S-LTD4 competed with (/sup 3/H)-LTD4. The metabolic inhibitors of arachidonic acid and SKF 88046, an antagonist of the indirectly-mediated actions of LTD4, did not significantly compete with (/sup 3/H)-LTD4 at the specific binding sites. These correlations indicated that these specific binding sites may be the putative leukotriene receptors in the guinea-pig lung.

• Research Organization: Smith Kline and French Labs., Philadelphia, PA
• OSTI ID: 5655782
• Journal Information: Prostaglandins; (United States), Vol. 28:6
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
METABOLITES
CHEMICAL BONDS
RECEPTORS
ARACHIDONIC ACID
BIOCHEMICAL REACTION KINETICS
BRAIN
CELL MEMBRANES
GUINEA PIGS
LIGANDS
LIVER
LUNGS
RABBITS
SMALL INTESTINE
TRACER TECHNIQUES
TRACHEA
TRITIUM COMPOUNDS
UTERUS
ANIMALS
BODY
CARBOXYLIC ACIDS
CELL CONSTITUENTS
CENTRAL NERVOUS SYSTEM
DIGESTIVE SYSTEM
FEMALE GENITALS
GASTROINTESTINAL TRACT
GLANDS
INTESTINES
ISOTOPE APPLICATIONS
KINETICS
LABELLED COMPOUNDS
MAMMALS
MEMBRANES
MONOCARBOXYLIC ACIDS
NERVOUS SYSTEM
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANS
REACTION KINETICS
RESPIRATORY SYSTEM
RODENTS
VERTEBRATES
550201* - Biochemistry- Tracer Techniques