Characterization of cholecystokinin receptors on guinea pig gastric chief cell membranes

Journal Article · Thu Feb 14 04:00:00 EST 1991 · Biochemical and Biophysical Research Communications; (USA)

DOI:https://doi.org/10.1016/0006-291X(91)91527-J· OSTI ID:5895475

Matozaki, T; Sakamoto, C; Nagao, M; Nishisaki, H; Konda, Y; Nakano, O; Matsuda, K; Wada, K; Suzuki, T; Kasuga, M ^[1]

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1. Kobe Univ. School of Medicine (Japan)

The binding of cholecystokinin (CCK) to its receptors on guinea pig gastric chief cell membranes were characterized by the use of {sup 125}I-CCK-octapeptide (CCK8). At 30{degrees}C optimal binding was obtained at acidic pH in the presence of Mg2+, while Na+ reduced the binding. In contrast to reports on pancreatic and brain CCK receptors, scatchard analysis of CCK binding to chief cell membranes revealed two classes of binding sites. Whereas, in the presence of a non-hydrolyzable GTP analog, GTP gamma S, only a low affinity site of CCK binding was observed. Chief cell receptors recognized CCK analogs, with an order of potency of: CCK8 greater than gastrin-I greater than CCK4. Although all CCK receptor antagonists tested (dibutyryl cyclic GMP, L-364718 and CR1409) inhibited labeled CCK binding to chief cell membranes, the relative potencies of these antagonists in terms of inhibiting labeled CCK binding were different from those observed in either pancreatic membranes or brain membranes. The results indicate, therefore, that on gastric chief cell membranes there exist specific CCK receptors, which are coupled to G protein. Furthermore, chief cell CCK receptors may be distinct from pancreatic or brain type CCK receptors.

• OSTI ID: 5895475
• Journal Information: Biochemical and Biophysical Research Communications; (USA), Journal Name: Biochemical and Biophysical Research Communications; (USA) Vol. 174:3; ISSN BBRCA; ISSN 0006-291X
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ANIMALS
BETA DECAY RADIOISOTOPES
BIOCHEMICAL REACTION KINETICS
CHEMICAL COMPOSITION
DAYS LIVING RADIOISOTOPES
DIGESTIVE SYSTEM
ELECTRON CAPTURE RADIOISOTOPES
GASTROINTESTINAL TRACT
GUINEA PIGS
INTERMEDIATE MASS NUCLEI
IODINE 125
IODINE ISOTOPES
ISOTOPES
KINETICS
KININS
MAMMALS
MEMBRANE PROTEINS
MEMBRANES
MUCOUS MEMBRANES
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
PEPTIDES
POLYPEPTIDES
PROTEINS
RADIOISOTOPES
REACTION KINETICS
RECEPTORS
RODENTS
VERTEBRATES