Comparative studies on behavioral neurochemical effects of N,α-diethylphenethylamine and methamphetamine in rats

One objective was to compare the psychostimulating effects of N,alpha-diethylphenethylamine (NADEP) with those of methamphetamine (METH) in experiments on behavioral activities of rats. Another objective was to compare concentrations of neurotransmitters dopamine (DA), serotonin (5-HT), and their metabolites such as dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), and 5-hydroxyindoleacetic acid (5-HIAA) in brain tissues (striatum and frontal cortex) carried out after administration of NADEP and METH in rats. The animals were treated with NADEP and METH for 6 consecutive days (5 mg/kg per day, respectively), and the scores of stereotypy were measured on the first, second, fourth, and sixth day. The increase of the stereotypy score was observed in the NADEP-treated group, but it was less than that after treatment with METH. NADEP administration (5 and 10 mg/kg) resulted in a significant increase of DA and 5-HT and a decrease of DOPAC and HVA in the striatum tissues, which were collected 1 h after administration, but the changes of the compounds were less than those after treatment with METH (5 mg/kg). Unlike the METH-treated group, the changed DA, 5-HT, DOPAC, and HVA levels of the NADEP- treated group (5 and 10 mg/kg) were soon recovered within 6 h after administration. Both NADEP and METH had no significant effect on the 5-HIAA concentrations of the brain tissues. These results suggest that NADEP has significant psychostimulatory effects, though the effects were less than those of METH. Thus, NADEP should be carefully monitored to avoid abuse as a psychoactive drug.