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

Drug Alcohol Depend. 2000 Aug 1;60(2):121-32. doi: 10.1016/s0376-8716(99)00148-9.


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.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Carbolines / chemistry
  • Carbolines / metabolism*
  • Cell Line
  • Hydrolysis
  • Inositol Phosphates / metabolism
  • N,N-Dimethyltryptamine / analogs & derivatives
  • N,N-Dimethyltryptamine / metabolism
  • Rats
  • Receptors, Dopamine D2 / metabolism*
  • Receptors, GABA-A / metabolism*
  • Receptors, Serotonin / metabolism*
  • Receptors, Serotonin, 5-HT1


  • Carbolines
  • Inositol Phosphates
  • Receptors, Dopamine D2
  • Receptors, GABA-A
  • Receptors, Serotonin
  • Receptors, Serotonin, 5-HT1
  • N,N-Dimethyltryptamine