Skip to content

Binding of beta-carbolines and related agents at serotonin (5-HT(2) and 5-HT(1A)), dopamine (D(2)) and benzodiazepine receptors.

Richard A Glennon, M Dukat, B Grella, S Hong, L Costantino, Milt Teitler, C Smith, C Egan, K Davis, M V Mattson

Drug and Alcohol Dependence August 1, 2000 DOI: 10.1016/s0376-8716(99)00148-9 (opens in new tab)

Study at a glance

AI-extracted from the abstract
Characteristics In vitro receptor binding study Peer reviewed
Topics Serotonin
Key points Beta-carbolines bind with modest affinity at 5-HT2A receptors, with affinity highly dependent on ring substituents and saturation, and show little to no affinity for 5-HT1A, dopamine D2, or (except beta-CCM) benzodiazepine receptors. The authors argue that, lacking enhanced agonist-labeled 5-HT2A affinity and agonist action in the PI hydrolysis assay, beta-carbolines are difficult to classify as behaving like classical hallucinogens.

Abstract

A large series of beta-carbolines was examined for their ability to bind at [3H]agonist-labeled 5-HT(2A) serotonin receptors. Selected beta-carbolines were also examined at 5-HT(2C) serotonin receptors, 5-HT(1A) serotonin receptors, dopamine D(2) receptors, and benzodiazepine receptors. Indolealkylamines and phenylisopropylamines were also evaluated in some of these binding assays. The beta-carbolines were found to bind with modest affinity at 5-HT(2A) receptors, and affinity was highly dependent upon the presence of ring substituents and ring saturation. The beta-carbolines displayed little to no affinity for 5-HT(1A) serotonin receptors, dopamine D(2) receptors and, with the exception of beta-CCM, for benzodiazepine receptors. Examples of beta-carbolines, indolealkylamines (i.e. N,N-dimethyltryptamine analogs), and phenylisopropylamines have been previously shown to produce common stimulus effects in animals trained to discriminate the phenylisopropylamine hallucinogen DOM (i.e. 1-(2, 5-dimethoxy-4-methylphenyl)-2-aminopropane) from vehicle. Although the only common receptor population that might account for this action is 5-HT(2A), on the basis of a lack of enhanced affinity for agonist-labeled 5-HT(2A) receptors, as well as on their lack of agonist action in the PI hydrolysis assay, it is difficult to conclude that the beta-carbolines behave in a manner consistent with that of other classical hallucinogens.

Comparable studies

Other preclinical and animal studies on serotonin, most cited first.

Citations in the library

Cited by 57

and 52 more in the library

Cites 8

and 3 more in the library

Explore topics