Increased caudate dopamine turnover may contribute to the recovery of motor function in marmosets treated with the dopaminergic neurotoxin MPTP.
Administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) to common marmosets initially impaired motor function, but a partial recovery occurred over the following weeks. At both 10 days and 4-6 weeks following MPTP treatment, [3H]dopamine ([3H]DA) uptake into synaptosomal preparations of putamen was markedly decreased. At 10 days and 4-6 weeks following MPTP treatment DA, homovanillic acid (HVA) and 3,4-dihydroxyphenylacetic acid (DOPAC) levels in the caudate nucleus and nucleus accumbens were substantially reduced. However, the levels of HVA and DOPAC in caudate nucleus were higher at 4-6 weeks than at 10 days. The ratio of (DOPAC + HVA)/DA in caudate nucleus was elevated at 10 days following MPTP treatment and even more so at 4-6 weeks. No change in Bmax or Kd values for [3H]spiperone binding to caudate preparations were observed. The recovery of motor function in marmosets observed following MPTP treatment may result partially from a compensatory increase in caudate DA turnover by remaining neurones.
Rose
S
S
Parkinson's Disease Society Research Centre, University Department of Neurology, Institute of Psychiatry, London, U.K.
Nomoto
M
M
Kelly
E
E
Kilpatrick
G
G
Jenner
P
P
Marsden
C D
CD
D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; D015102:3,4-Dihydroxyphenylacetic Acid / Q000378:metabolism; D000818:Animals; D002143:Callitrichinae / Q000378:metabolism*; D002421:Caudate Nucleus / Q000378:metabolism* / Q000503:physiopathology; D004298:Dopamine / Q000378:metabolism*; D006719:Homovanillic Acid / Q000378:metabolism; D008297:Male; D009498:Neurotoxins / Q000494:pharmacology; D010302:Parkinson Disease, Secondary / Q000378:metabolism* / Q000503:physiopathology; D011725:Pyridines / Q000633:toxicity*; D013997:Time Factors
D009498:Neurotoxins; D011725:Pyridines; D015102:3,4-Dihydroxyphenylacetic Acid; D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; D004298:Dopamine; D006719:Homovanillic Acid