The effect of the alkaloid (-)cathinone on the motor activity in mice.

Khat leaves, widely used as a stimulant in East Africa and the Arab Peninsula, contain the alkaloid, (-)cathinone. This substance was found to cause in mice an increase of locomotor activity characterized by a dose-effect relationship typical for amphetamine. Furthermore, the effect of (-)cathinone was inhibited by pretreatment of the animals with the neuroleptics haloperidol, spiroperidol, pimozide, flupentixol and butaclamol. Pretreatment with reserpine reduced the effect of (-)cathinone moderately; in reserpinized mice the effect of (-)cathinone was antagonized by the uptake inhibitors mazindol and nomifensine. Together, these observations indicate that the pharmacology of (-)cathinone hypermotility closely parallels that of amphetamine hypermotility. The results suggest that the stimulating properties of khat leaves are due to the presence of an alkaloid with amphetamine-like effects.