High density of benzodiazepine binding sites in the substantia innominata of the rat

Journal Article · Fri Jul 01 00:00:00 EDT 1988 · Pharmacol., Biochem. Behav.; (United States)

DOI:https://doi.org/10.1016/0091-3057(88)90083-4· OSTI ID:6354142

Sarter, M; Schneider, H H

In order to study the neuronal basis of the pharmacological interactions between benzodiazepine receptor ligands and cortical cholinergic turnover, we examined the regional distribution of specific benzodiazepine binding sites using in vitro autoradiography. In the basal forebrain, the substantia innominata contained a high density of (/sup 3/H)lormetazepam (LMZ) binding sites (Bmax = 277 fmol/mg tissue; Kd = 0.55 nM). The label could be displaced by diazepam (IC50 = 100 nM), the benzodiazepine receptor antagonist beta-carboline ZK 93426 (45 nM) and the partial inverse agonist beta-carboline FG 7142 (540 nM). It is hypothesized that the amnesic effects of benzodiazepine receptor agonists are exerted through benzodiazepine receptors which are situated on cholinergic neurons in the substantia innominata and are involved in a tonic inhibition of cortical acetylcholine release. The benzodiazepine receptor antagonist ZK 93426 may exert its nootropic effects via benzodiazepine receptors in the substantia innominata and, consequently, by disinhibiting cortical acetylcholine release.

• Research Organization: Research Laboratories of Schering AG, Berlin and Bergkamen (Germany, F.R.)
• OSTI ID: 6354142
• Journal Information: Pharmacol., Biochem. Behav.; (United States), Vol. 30:3
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
ACETYLCHOLINE
BIOCHEMICAL REACTION KINETICS
RECEPTORS
SPECIFICITY
SYMPATHOLYTICS
AUTORADIOGRAPHY
BRAIN
LIGANDS
NERVES
RATS
SECRETION
TRITIUM COMPOUNDS
AMINES
AMMONIUM COMPOUNDS
ANIMALS
AUTONOMIC NERVOUS SYSTEM AGENTS
BODY
CENTRAL NERVOUS SYSTEM
DRUGS
ESTERS
KINETICS
LABELLED COMPOUNDS
MAMMALS
MEMBRANE PROTEINS
NERVOUS SYSTEM
NEUROREGULATORS
ORGANIC COMPOUNDS
ORGANS
PARASYMPATHOMIMETICS
PROTEINS
QUATERNARY COMPOUNDS
REACTION KINETICS
RODENTS
VERTEBRATES
550201* - Biochemistry- Tracer Techniques