[Effect of beta-phenylethylamine on locomotor activity and brain catecholamine metabolism in mice]

beta-Phenylethylamine (PEA) is a naturally occurring compound and its structure is close to amphetamine. The effects of PEA on locomotor activity and brain catecholamine metabolism in mice were investigated. Mice were injected with PEA 50 mg/kg intraperitoneally. PEA produced increased locomotor activity between 3 and 6 min, then a decline to 20 min after the injection. There was decreased activity with a slight stereotyped behavior consisted of sniffing and head bobbing between 15 and 20 min. 3-Methoxy-4-hydroxy-phenylethyleneglycol (MHPG), homovanillic acid (HVA) and 3,4-dihydroxyphenylacetic acid (DOPAC) levels in the whole brain were examined. MHPG levels showed no remarkable changes at 5 min after PEA, then increase at 30 and 60 min. HVA level was increased but DOPAC level was decreased at 60 min. Type B monoamine oxidase activity showed no remarkable changes in discrete regions of the brain at 5 and 30 min. These results suggest that PEA may not only release catecholamines but inhibit the reuptake of neurogenically released dopamine.