Binding of /sup 3/H-acetylcholine to cholinergic receptors in bovine cerebral arteries

Journal Article · Sun Nov 17 23:00:00 EST 1985 · Life Sci.; (United States)

DOI:https://doi.org/10.1016/0024-3205(85)90006-2· OSTI ID:6138596

Shimohama, S; Tsukahara, T; Taniguchi, T; Fujiwara, M

Cholinergic receptor sites in bovine cerebral arteries were analyzed using radioligand binding techniques with the cholinergic agonist, /sup 3/H-acetylcholine (ACh), as the ligand. Specific binding of /sup 3/H-ACh to membrane preparations of bovine cerebral arteries was saturable, of two binding sites, with dissociation constant (K/sub D/) values of 0.32 and 23.7 nM, and maximum binding capacity (Bmax) values of 67 and 252 fmol/mg protein, respectively. Specific binding of /sup 3/H-ACh was displaced effectively by muscarinic cholinergic agents and less effectively by nicotinic cholinergic agents. IC/sub 50/ values of cholinergic drugs for /sup 3/H-ACh binding were as follows: atropine, 38.5 nM; ACh, 59.8 nM; oxotremorine, 293 nM; scopolamine 474 nM; carbamylcholine, 990 nM. IC/sub 50/ values of nicotinic cholinergic agents such as nicotine, cytisine and ..cap alpha..-bungarotoxin exceeded 50 ..mu..M. Choline acetyltransferase activity was 1.09 nmol/mg protein/hour in the cerebral arteries. These findings suggest that the cholinergic nerves innervate the bovine cerebral arteries and that there are at least two classes of ACh binding sites of different affinities on muscarinic reporters in these arteries. 18 references, 2 figures, 2 tables.

• Research Organization: Kyoto Univ., Japan
• OSTI ID: 6138596
• Journal Information: Life Sci.; (United States), Journal Name: Life Sci.; (United States) Vol. 37:20; ISSN LIFSA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ACETYLCHOLINE
AFFINITY
ALCOHOLS
ALKALOIDS
AMINES
AMMONIUM COMPOUNDS
ANIMALS
ARTERIES
ATROPINE
AUTONOMIC NERVOUS SYSTEM AGENTS
AZINES
AZOLES
BIOCHEMICAL REACTION KINETICS
BLOOD VESSELS
BODY
BRAIN
CARDIOVASCULAR SYSTEM
CATTLE
CELL CONSTITUENTS
CELL MEMBRANES
CENTRAL NERVOUS SYSTEM
CHEMICAL BONDS
CHOLINE
DATA
DOMESTIC ANIMALS
DRUGS
ENZYME ACTIVITY
ENZYMES
ESTERS
EXPERIMENTAL DATA
HETEROCYCLIC COMPOUNDS
HYDROXY COMPOUNDS
INFORMATION
ISOTOPE APPLICATIONS
KINETICS
LABELLED COMPOUNDS
LIGANDS
LIPOTROPIC FACTORS
MAMMALS
MEMBRANE PROTEINS
MEMBRANES
NERVES
NERVOUS SYSTEM
NEUROREGULATORS
NICOTINE
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANS
PARASYMPATHOLYTICS
PARASYMPATHOMIMETICS
PROTEINS
PYRIDINES
PYRROLES
PYRROLIDINES
QUATERNARY COMPOUNDS
REACTION KINETICS
RECEPTORS
RUMINANTS
TRACER TECHNIQUES
TRANSFERASES
TRITIUM COMPOUNDS
VERTEBRATES