Notes on buspirone's mechanisms of action.

Buspirone is a novel psychotropic drug with clear anxiolytic activity in man. There are a number of neurochemical differences between buspirone and both neuroleptics and benzodiazepines. Moreover, buspirone is extensively metabolized, and several metabolites are present in the brain together with the parent compound. One of these, 1-PP, is present in the brain at higher concentrations than the parent drug, particularly when the drug is given orally. On the basis of the reported experimental data, it can be postulated that buspirone's anticonflict activity in rats may be mediated, at least partially, through 1-PP, without involving any effect on the dopaminergic system. The possibility that buspirone and 1-PP may mimic the action of benzodiazepine on some sites in the complex benzodiazepine-GABA receptors is discussed.