Biochemical aspects of Parkinson-dementia complex.
Positron emission tomography of a parkinsonian patient with dementia revealed a decreased cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRO2) in the cerebral cortex and deep gray matter, whereas a parkinsonian patient without dementia showed a decrease in CBF and CMRO2 in the deep gray matter, but not in the cerebral cortex. The ratio of 3,4-dihydroxyphenylacetic acid/L-dopa in the plasma after L-dopa administration was significantly increased in parkinsonian patients with hallucinations, indicating an accelerated metabolism of L-dopa. The concentration of 5-hydroxyindoleacetic acid (5HIAA) was decreased in the cerebrospinal fluid of parkinsonian patients with psychiatric symptoms, especially with visual hallucinations. The serotonin level in mouse striatum was significantly reduced 1 week after methylphenyltetrahydropyridine (MPTP) injection, though returned to normal in 4 weeks. The 5HIAA level increased at both 1 and 4 weeks. The activity of tryptophan hydroxylase was increased in the striatum 1-4 weeks after MPTP injection, but was unchanged in the cerebral cortex. The choline acetyltransferase (ChAT) activity was significantly decreased in the hippocampus 1 week, but not 4 weeks after MPTP. The ChAT activity was not changed in the frontal cortex at either 1 or 4 weeks.
Nakamura
S
S
Department of Neurology, Faculty of Medicine, Kyoto University, Japan.
Fukuda
H
H
Hara
K
K
Fukuyama
H
H
Kameyama
M
M
D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; D015102:3,4-Dihydroxyphenylacetic Acid / Q000097:blood; D000818:Animals; D001921:Brain / Q000378:metabolism*; D003704:Dementia / Q000150:complications / Q000378:metabolism*; D005260:Female; D006801:Humans; D007980:Levodopa / Q000097:blood / Q000378:metabolism; D008297:Male; D051379:Mice; D008875:Middle Aged; D010100:Oxygen / Q000378:metabolism; D010300:Parkinson Disease / Q000150:complications / Q000378:metabolism*; D011725:Pyridines / Q000494:pharmacology; D012701:Serotonin / Q000378:metabolism; D014365:Tryptophan Hydroxylase / Q000378:metabolism
D011725:Pyridines; D015102:3,4-Dihydroxyphenylacetic Acid; D012701:Serotonin; D007980:Levodopa; D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; D014365:Tryptophan Hydroxylase; D010100:Oxygen