Bovine gallbladder muscularis: Source of a myogenic receptor for cholecystokinin

Journal Article · Mon Feb 29 23:00:00 EST 1988 · American Journal of Physiology; (USA)

OSTI ID:6810507

Schjoldager, B; Shaw, M J; Powers, S P; Schmalz, P E; Szurszewski, J; Miller, L J ^[1]

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1. Mayo Clinic and Foundation, Rochester, MN (USA)

Despite being a classic target for the gastrointestinal peptide hormone, cholecystokinin (CCK), the gallbladder CCK receptor is not well characterized. Pharmacological studies of small species suggest that CCK action can be mediated by direct myogenic or by both myogenic and neurogenic receptors. To prepare for the biochemical characterization of a gallbladder CCK receptor and to define the subtype of the receptor being studied. The authors have performed autoradiographic localization and pharmacological characterization of CCK receptors on bovine gallbladder. Autoradiography demonstrated high-affinity specific CCK-binding sites only on the muscularis. CCK-8 stimulated tonic contraction of longitudinal strips of gallbladder muscularis in a concentration-dependent manner. Antagonism at the cholinergic receptor with 1{mu}M atropine or axonal transmission with 1{mu}M tetrodotoxin did not modify CCK-induced contraction, supporting a direct myogenic effect of this hormone. Optimal electrical field stimulation to elicit a neuronal response resulted in muscle strip relaxation, which was abolished with adrenergic blockade. Although acetylcholine administration stimulated contraction, electrical field stimulation did not, even in the presence of phentolamine, propranolol, and/or CCK. Thus, in bovine gallbladder muscularis, there is evidence for a functional CCK receptor only on smooth muscle cells. Demonstration of a single, high-affinity specific CCK-binding site on an enriched plasma membrane preparation of bovine gallbladder muscularis is consistent with this representing a myogenic CCK receptor.

• OSTI ID: 6810507
• Journal Information: American Journal of Physiology; (USA), Journal Name: American Journal of Physiology; (USA) Vol. 254:3; ISSN 0002-9513; ISSN AJPHA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ANIMALS
AUTORADIOGRAPHY
BETA DECAY RADIOISOTOPES
BILIARY TRACT
CATTLE
DAYS LIVING RADIOISOTOPES
DIGESTIVE SYSTEM
DISTRIBUTION
DOMESTIC ANIMALS
ELECTRON CAPTURE RADIOISOTOPES
INTERMEDIATE MASS NUCLEI
IODINE 125
IODINE ISOTOPES
ISOTOPES
KININS
LIGANDS
MAMMALS
MEMBRANE PROTEINS
MUSCLES
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
PEPTIDES
PHARMACOLOGY
POLYPEPTIDES
PROTEINS
RADIOISOTOPES
RECEPTORS
RUMINANTS
TISSUE DISTRIBUTION
VERTEBRATES