1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) enhances tryptophan hydroxylase activity in mouse striatum, but not in the frontal cortex.
We measured serotonin (5-HT) and 5-hydroxyindole-3-acetic acid (5-HIAA) contents and tryptophan hydroxylase (TPH) activity in mouse striatum and frontal cortex after 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) treatment (7 daily injections of 30 mg/kg). In the striatum, TPH activity was increased for at least 4 weeks after injection of MPTP, along with an increase in 5-HIAA. However, no significant change was observed in 5-HT, 5-HIAA or TPH activity in the frontal cortex. These results suggest that MPTP affects 5-HT through a change in TPH activity, specifically at nerve terminals in the striatum.
Fukuda
H
H
Department of Neurology, Faculty of Medicine, Kyoto University, Japan.
Hara
K
K
Nakamura
S
S
Kimura
H
H
Kameyama
M
M
D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; D000818:Animals; D002540:Cerebral Cortex / Q000187:drug effects / Q000201:enzymology*; D003342:Corpus Striatum / Q000187:drug effects / Q000201:enzymology*; D004298:Dopamine / Q000378:metabolism; D006897:Hydroxyindoleacetic Acid / Q000378:metabolism; D007700:Kinetics; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D009928:Organ Specificity; D011725:Pyridines / Q000494:pharmacology*; D012016:Reference Values; D012701:Serotonin / Q000378:metabolism; D014365:Tryptophan Hydroxylase / Q000378:metabolism*
D011725:Pyridines; D012701:Serotonin; D006897:Hydroxyindoleacetic Acid; D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; D014365:Tryptophan Hydroxylase; D004298:Dopamine