Cathinone, cocaine and methamphetamine: similarity of behavioral effects

The discriminative stimulus properties of (+/-)-cathinone were tested by training eight rats to discriminate between the interoceptive cues produced by 0.6 mg/kg (+/-)-cathinone and saline in a food-reinforced, two lever operant task. Doses of cocaine and methamphetamine were observed to transfer to the cathinone cue and all three drugs exhibited decreased discriminative performance with decreasing doses. The ED50 for (+/-)-cathinone, (+/-)-methamphetamine and cocaine were 0.23, 0.17, and 1.97 mg/kg, respectively, and the three curves were shown to be parallel. These data indicate the possibility of a common mechanism/site of action for these three stimulants, presumably by their actions upon central dopaminergic neurons.