title: Effect of beta-phenylethylamine on extracellular concentrations of dopamine in the nucleus accumbens and prefrontal cortex.
abstract: It is known that psychostimulants stimulate dopamine transmission in the nucleus accumbens. In the present study, we examined the effects of systemically administered beta-phenylethylamine (beta-PEA), a psychomotor-stimulating trace amine, on dopamine concentrations in the nucleus accumbens and prefrontal cortex in freely moving rats, using an in vivo microdialysis technique. Intraperitoneal administration of beta-PEA (12.5 and 25 mg/kg) significantly increased extracellular dopamine levels in the nucleus accumbens shell. The observed increase in the dopamine concentration in nucleus accumbens shell dialysate after intraperitoneal administration of 25 mg/kg beta-PEA was inhibited by pre-treatment with a dopamine uptake inhibitor, GBR12909 (10 mg/kg, i.p.). In contrast, beta-PEA (25 mg/kg, i.p.) did not affect dopamine release in the nucleus accumbens core. Although a high dose of beta-PEA (50 mg/kg) significantly increased dopamine levels in the nucleus accumbens core, the dopamine increasing effect of beta-PEA was more potent in the nucleus accumbens shell. Systemic administration of 12.5 and 25 mg/kg beta-PEA also increased extracellular dopamine levels in the prefrontal cortex of rats. However, systemic 25 mg/kg beta-PEA-induced increases in extracellular dopamine levels were not blocked by GBR12909 within the prefrontal cortex. These results suggest that beta-PEA has a greater effect in the shell than in the core and low-dose beta-PEA stimulates dopamine release in the nucleus accumbens shell through uptake by a dopamine transporter. Similarly, beta-PEA increased extracellular dopamine levels in the prefrontal cortex. Thus, beta-PEA may increase extracellular dopamine concentrations in the mesocorticolimbic pathway.
authors.affiliation: Department of Medicinal Pharmacology, Showa Pharmaceutical University, 3-3165 Higashitamagawagakuen, Machida, Tokyo 194-0042, Japan.
authors.forename: Mikio
authors.initials: M
authors.lastname: Murata
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Katagiri
authors.forename: Kota
authors.initials: K
authors.lastname: Ishida
authors.forename: Kenji
authors.initials: K
authors.lastname: Abe
authors.forename: Masago
authors.initials: M
authors.lastname: Ishikawa
authors.forename: Iku
authors.initials: I
authors.lastname: Utsunomiya
authors.forename: Keiko
authors.initials: K
authors.lastname: Hoshi
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Miyamoto
authors.forename: Kyoji
authors.initials: K
authors.lastname: Taguchi
mesh_terms: D000818:Animals; D004298:Dopamine / Q000378:metabolism*; D018765:Dopamine Uptake Inhibitors / Q000494:pharmacology; D005110:Extracellular Space / Q000378:metabolism; D007274:Injections, Intraperitoneal; D008297:Male; D017551:Microdialysis; D009714:Nucleus Accumbens / Q000187:drug effects* / Q000378:metabolism; D010627:Phenethylamines / Q000494:pharmacology*; D010879:Piperazines / Q000494:pharmacology; D017397:Prefrontal Cortex / Q000187:drug effects* / Q000378:metabolism; D011619:Psychotropic Drugs / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D018765:Dopamine Uptake Inhibitors; D010627:Phenethylamines; D010879:Piperazines; D011619:Psychotropic Drugs; C029261:phenethylamine; C043425:vanoxerine; D004298:Dopamine