Abstract
Differential pulse voltammetry with carbon fiber electrodes was used to study serotonin (5-HT) metabolism in freely moving rats. The electrodes implanted in the striatum recorded the extracellular 5-hydroxyindoleacetic acid (5-HIAA) oxidation peak after oral tryptophan (150 mg/kg). This 5-HT precursor did not modify the 5-HIAA peak in any rat tested, but it raised 5-HIAA levels determined in total tissue by a classical biochemical method (HPLC). The administration of 5-hydroxytryptophan (5-HTP) (25 mg/kg i.p.) induced an increase of 5-HIAA detectable both in the extracellular medium by voltammetry and in tissue samples. As previously shown, dorsal raphe electrical stimulation raises extracellular 5-HIAA in the striatum and this effect is enhanced by pretreatment with tryptophan. The results suggest that tryptophan in 'normal' conditions enhances 5-HT metabolism without affecting 5-HT release unless such release is stimulated. 5-HTP increases 5-HT metabolism and release.
| Original language | English |
|---|---|
| Pages (from-to) | 89-94 |
| Number of pages | 6 |
| Journal | Brain Research |
| Volume | 411 |
| Issue number | 1 |
| DOIs | |
| Publication status | Published - May 12 1987 |
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Keywords
- High-pressure liquid chromatography (HPLC)
- In vivo voltammetry
- Serotonin metabolism
- Truptophan
ASJC Scopus subject areas
- Developmental Biology
- Molecular Biology
- Clinical Neurology
- Neuroscience(all)
Cite this
Functional meaning of tryptophan-induced increase of 5-HT metabolism as clarified by in vivo voltammetry. / De Simoni, Maria Grazia; Sokola, Andrzej; Fodritto, Fabio; Toso, Giuseppe Dal; Algeri, Sergio.
In: Brain Research, Vol. 411, No. 1, 12.05.1987, p. 89-94.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Functional meaning of tryptophan-induced increase of 5-HT metabolism as clarified by in vivo voltammetry
AU - De Simoni, Maria Grazia
AU - Sokola, Andrzej
AU - Fodritto, Fabio
AU - Toso, Giuseppe Dal
AU - Algeri, Sergio
PY - 1987/5/12
Y1 - 1987/5/12
N2 - Differential pulse voltammetry with carbon fiber electrodes was used to study serotonin (5-HT) metabolism in freely moving rats. The electrodes implanted in the striatum recorded the extracellular 5-hydroxyindoleacetic acid (5-HIAA) oxidation peak after oral tryptophan (150 mg/kg). This 5-HT precursor did not modify the 5-HIAA peak in any rat tested, but it raised 5-HIAA levels determined in total tissue by a classical biochemical method (HPLC). The administration of 5-hydroxytryptophan (5-HTP) (25 mg/kg i.p.) induced an increase of 5-HIAA detectable both in the extracellular medium by voltammetry and in tissue samples. As previously shown, dorsal raphe electrical stimulation raises extracellular 5-HIAA in the striatum and this effect is enhanced by pretreatment with tryptophan. The results suggest that tryptophan in 'normal' conditions enhances 5-HT metabolism without affecting 5-HT release unless such release is stimulated. 5-HTP increases 5-HT metabolism and release.
AB - Differential pulse voltammetry with carbon fiber electrodes was used to study serotonin (5-HT) metabolism in freely moving rats. The electrodes implanted in the striatum recorded the extracellular 5-hydroxyindoleacetic acid (5-HIAA) oxidation peak after oral tryptophan (150 mg/kg). This 5-HT precursor did not modify the 5-HIAA peak in any rat tested, but it raised 5-HIAA levels determined in total tissue by a classical biochemical method (HPLC). The administration of 5-hydroxytryptophan (5-HTP) (25 mg/kg i.p.) induced an increase of 5-HIAA detectable both in the extracellular medium by voltammetry and in tissue samples. As previously shown, dorsal raphe electrical stimulation raises extracellular 5-HIAA in the striatum and this effect is enhanced by pretreatment with tryptophan. The results suggest that tryptophan in 'normal' conditions enhances 5-HT metabolism without affecting 5-HT release unless such release is stimulated. 5-HTP increases 5-HT metabolism and release.
KW - High-pressure liquid chromatography (HPLC)
KW - In vivo voltammetry
KW - Serotonin metabolism
KW - Truptophan
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U2 - 10.1016/0006-8993(87)90684-6
DO - 10.1016/0006-8993(87)90684-6
M3 - Article
C2 - 2440515
AN - SCOPUS:0023181339
VL - 411
SP - 89
EP - 94
JO - Brain Research
JF - Brain Research
SN - 0006-8993
IS - 1
ER -