In vivo release of endogenous dopamine, 5-hydroxytryptamine and some of their metabolites from rat caudate nucleus by phenylethylamine

Neurochem Res. 1987 Feb;12(2):173-8. doi: 10.1007/BF00979534.


The in vivo release of endogenous 3,4-dihydroxyphenylethylamine (DA) and its metabolites, 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA) and 3-methoxytyramine (3-MT), and of 5-hydroxytryptamine (5-HT) and its metabolite, 5-hydroxyindoleacetic acid (5-HIAA), has been measured in the caudate nucleus of the anesthetized rat. A push-pull cannula was implanted into the brain, and the tissue perfused with artificial CSF or artificial CSF containing 5 X 10(-4) M phenylethylamine. The perfusate was collected and analyzed for DA, 5-HT and their metabolites by high performance liquid chromatography with electrochemical detection (HPLC-ECD). DA was released by phenylethylamine at rates significantly greater than its basal rate. 3-MT and 5-HT were undetectable in perfusates collected under basal conditions, but could be detected readily during phenylethylamine stimulation. DOPAC, HVA and 5-HIAA concentrations were not significantly affected by phenylethylamine. The results suggest (1) that phenylethylamine may exert its behavioural effects through increased release of both DA and 5-HT, and (2) that in vivo measurements of the acid metabolites alone may not be indicative of the release of the amines.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3,4-Dihydroxyphenylacetic Acid / analysis
  • Animals
  • Caudate Nucleus / drug effects*
  • Caudate Nucleus / metabolism
  • Chromatography, High Pressure Liquid
  • Dopamine / analogs & derivatives
  • Dopamine / analysis
  • Dopamine / metabolism*
  • Homovanillic Acid / analysis
  • Hydroxyindoleacetic Acid / analysis
  • Male
  • Phenethylamines / pharmacology*
  • Rats
  • Rats, Inbred Strains
  • Serotonin / metabolism*


  • Phenethylamines
  • 3,4-Dihydroxyphenylacetic Acid
  • phenethylamine
  • Serotonin
  • Hydroxyindoleacetic Acid
  • 3-methoxytyramine
  • Dopamine
  • Homovanillic Acid