Characterization and autoradiographic localization of multiple tachykinin binding sites in gastrointestinal tract and bladder

Journal Article · Sat Mar 01 04:00:00 EST 1986 · J. Pharmacol. Exp. Ther.; (United States)

OSTI ID:5531928

Burcher, E; Buck, S H; Lovenberg, W; O'Donohue, T L

Binding sites for the (125I)Bolton-Hunter-labeled tachykinins substance K (BHSK), eledoisin (BHE) and substance P (BHSP) were investigated using crude membrane suspensions and autoradiography. In smooth muscle membranes from guinea-pig small intestine and rat duodenum, specific binding of BHSK was saturable and reversible, showing a single class of sites with a KD of 1 to 3 nM and maximum number of specific binding sites of 1 to 2 fmol/mg of wet weight tissue. Pharmacological characterization of this binding revealed a novel receptor site (K) with affinity for substance K greater than kassinin greater than or equal to eledoisin greater than neuromedin K greater than substance P greater than physalaemin. Inhibition of the binding of BHSK in membranes from mouse urinary bladder exhibited a similar K-type pattern. In rat duodenum and mouse bladder membranes, the binding of BHE was inhibited by substance K greater than kassinin greater than eledoisin greater than neuromedin K greater than substance P greater than physalaemin indicating the same receptor site as for BHSK. In rat cerebral cortex membranes BHE binding was inhibited by neuromedin K = kassinin = eledoisin greater than physalaemin greater than substance K greater than substance P indicating a definitive tachykinin E receptor site. The same displacement pattern of BHE binding was also detected in longitudinal muscle membranes from the guinea-pig small intestine. In mouse bladder membranes and in rat and guinea-pig intestine, the binding of BHSP was inhibited by substance P greater than physalaemin greater than substance K greater than or equal to eledoisin = kassinin greater than neuromedin K indicating a definitive tachykinin P receptor site. Autoradiographic binding sites for both BHSK and BHSP were seen in circular muscle of the rat stomach, small intestine and colon and in circular and longitudinal muscle of the guinea-pig small intestine and colon.

• Research Organization: National Institute of Neurological and Communicative Disorders and Stroke, Bethesda, MD
• OSTI ID: 5531928
• Journal Information: J. Pharmacol. Exp. Ther.; (United States), Journal Name: J. Pharmacol. Exp. Ther.; (United States) Vol. 3; ISSN JPETA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ANIMALS
AUTORADIOGRAPHY
BLADDER
BODY
BRAIN
CELL CONSTITUENTS
CELL MEMBRANES
CENTRAL NERVOUS SYSTEM
CEREBRAL CORTEX
CEREBRUM
DIGESTIVE SYSTEM
GASTROINTESTINAL TRACT
GUINEA PIGS
IN VITRO
KININS
MAMMALS
MEMBRANE PROTEINS
MEMBRANES
MICE
NERVOUS SYSTEM
ORGANIC COMPOUNDS
ORGANS
PEPTIDES
POLYPEPTIDES
PROTEINS
RATS
RECEPTORS
RODENTS
URINARY TRACT
VERTEBRATES