Characterization of muscarinic receptor subtypes in human tissues
The affinities of selective, pirenzepine and AF-DX 116, and classical, N-methylscopolamine and atropine, muscarinic cholinergic receptor antagonists were investigated in displacement binding experiments with (/sup 3/H)Pirenzepine and (/sup 3/H)N-methylscopolamine in membranes from human autoptic tissues (forebrain, cerebellum, atria, ventricle and submaxillary salivary glands). Affinity estimates of N-methylscopolamine and atropine indicated a non-selective profile. Pirenzepine showed differentiation between the M/sub 1/ neuronal receptor of the forebrain and the receptors in other tissues while AF-DX 116 clearly discriminated between muscarinic receptors of heart and glands. The results in human tissues confirm the previously described selectivity profiles of pirenzepine and AF-DX 116 in rat tissues. These findings thus reveal the presence also in man of three distinct muscarinic receptor subtypes: the neuronal M/sub 1/, the cardiac M/sub 2/ and the glandular M/sub 3/.
- Research Organization:
- Istituto de Angeli S.p.A., Milan (Italy)
- OSTI ID:
- 7055693
- Journal Information:
- Life Sci.; (United States), Vol. 43:19
- Country of Publication:
- United States
- Language:
- English
Similar Records
Regional distribution of M1, M2 and non-M1, non-M2 subtypes of muscarinic binding sites in rat brain
Heterogeneity of muscarinic receptor subtypes in cerebral blood vessels
Related Subjects
CHOLINE
RECEPTORS
PARASYMPATHOLYTICS
BIOCHEMICAL REACTION KINETICS
AFFINITY
BRAIN
CELL MEMBRANES
MAN
NERVES
SALIVARY GLANDS
TRACER TECHNIQUES
TRITIUM COMPOUNDS
ALCOHOLS
AMINES
AMMONIUM COMPOUNDS
ANIMALS
AUTONOMIC NERVOUS SYSTEM AGENTS
BODY
CELL CONSTITUENTS
CENTRAL NERVOUS SYSTEM
DRUGS
GLANDS
HYDROXY COMPOUNDS
ISOTOPE APPLICATIONS
KINETICS
LABELLED COMPOUNDS
LIPOTROPIC FACTORS
MAMMALS
MEMBRANE PROTEINS
MEMBRANES
NERVOUS SYSTEM
ORGANIC COMPOUNDS
ORGANS
PRIMATES
PROTEINS
QUATERNARY COMPOUNDS
REACTION KINETICS
VERTEBRATES
550201* - Biochemistry- Tracer Techniques