COCAINE AS A NATURALLY-OCCURRING INSECTICIDE

Although cocaine has a fascinating and complex medicinal history in ma n, its natural function in plants is unknown. The present studies demo nstrate that cocaine exerts insecticidal effects at concentrations whi ch occur naturally in coca leaves. Unlike its known action on dopamine reuptake in mammals, cocaine's pesticidal effects are shown to result from a potentiation of insect octopaminergic neurotransmission. Amine -reuptake blockers of other structural classes also exert pesticidal a ctivity with a rank order of potency distinct from that known to affec t vertebrate amine transporters. These findings suggest that cocaine f unctions in plants as a natural insecticide and that octopamine transp orters may be useful sites for targeting pesticides with selectivity t oward invertebrates.