Skip to main content
OSTI.GOVU.S. Department of Energy Office of Scientific and Technical Information
U.S. Department of Energy
Office of Scientific and Technical Information
 

Binding sites for /sup 3/H-LTC4 in membranes from guinea pig ileal longitudinal muscle

Journal Article · · Prostaglandins; (United States)
OSTI ID:6306017
; ; ;

Leutriene (LTC4) is one of the components of Slow Reacting Substance of Anaphylaxis (SRS-A) and is a potent constrictor of guinea pig ilea. The contraction is likely to be a receptor-mediated process. Here the authors report the existence of specific binding sites for /sup 3/H-LTC4 in a crude membrane preparation from guinea pig ileal longitudinal muscle. At 4 degrees C in the presence of 20 mM Serine-borate, binding increases linearly with protein concentration, reaches equilibrium in 10 minutes, and is reversible upon addition of 3 x 10(-5) M unlabelled LTC4. The dissociation curve is consistent with the existence of more than one class of binding site. Ca++ and Mg++ greatly enhance the binding of /sup 3/H-LTC4 at equilibrium. In the presence of 5 mM CaCl/sub 2/ and MgCl/sub 2/ not only LTC4 (IC50 10(-7)M), but also LTD4 and the SRS-A antagonist FPL 55712 can compete with /sup 3/H-LTC4 for its binding sites. FPL 55712 only displaces 60-70% of the total amount bound, while LTC4 displaces 90-95%. These studies indicate that multiple classes of binding sites exist for /sup 3/H-LTC4 in guinea pig ileal longitudinal muscle, and that at least part of these binding sites might be related to the ability of LTC4 to contract guinea pig ilea.

Research Organization:
Univ. of Milan, Italy
OSTI ID:
6306017
Journal Information:
Prostaglandins; (United States), Journal Name: Prostaglandins; (United States) Vol. 27:3; ISSN PRGLB
Country of Publication:
United States
Language:
English

Similar Records

Characterization of (/sup 3/H)leukotriene D4 binding sites in guinea-pig ventricular myocardium
Journal Article · Sat Jun 01 00:00:00 EDT 1985 · J. Pharmacol. Exp. Ther.; (United States) · OSTI ID:5253918
Identification of leukotriene D4 specific binding sites in the membrane preparation isolated from guinea pig lung
Journal Article · Fri Nov 30 23:00:00 EST 1984 · Prostaglandins; (United States) · OSTI ID:5655782
Characterization of guinea pig myocardial leukotriene C4 binding sites. Regulation by cations and sulfhydryl-directed reagents
Journal Article · Thu Jan 31 23:00:00 EST 1985 · Mol. Pharmacol.; (United States) · OSTI ID:5609804

Related Subjects

551001* -- Physiological Systems-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ALKALINE EARTH METAL COMPOUNDS
ANIMALS
BIOCHEMICAL REACTION KINETICS
BODY
CALCIUM CHLORIDES
CALCIUM COMPOUNDS
CALCIUM HALIDES
CELL CONSTITUENTS
CELL MEMBRANES
CHLORIDES
CHLORINE COMPOUNDS
CONTRACTION
DIGESTIVE SYSTEM
GASTROINTESTINAL TRACT
GUINEA PIGS
HALIDES
HALOGEN COMPOUNDS
INTESTINES
KINETICS
LABELLED COMPOUNDS
MAGNESIUM CHLORIDES
MAGNESIUM COMPOUNDS
MAMMALS
MEMBRANES
MUSCLES
ORGANS
PROSTAGLANDINS
REACTION KINETICS
RECEPTORS
RODENTS
SMALL INTESTINE
TRITIUM COMPOUNDS
VERTEBRATES