Olfactory impairment and Parkinson's disease-like symptoms observed in the common marmoset following administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine.
OBJECTIVE
Although olfactory disturbance appears to occur in the early stages of Parkinson's disease (PD) in humans, little is known about its mechanism. The aim of this study was to make a PD model using injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in the common marmoset and to discover the mechanism of olfactory disturbance in this animal.


METHODS
Olfactory disturbance induced by MPTP in the common marmoset was observed by behavioral, biochemical and immunohistochemical means.


RESULTS
Administration of MPTP caused common marmosets to enter an akinetic state within a few days and to show signs of impaired olfactory function. Biochemical study showed a decrease in dopamine levels, especially in tissue samples from the caudate nucleus and putamen. Immunohistochemical analysis revealed a lack of tyrosine hydroxylase immunoreactivity, not only in the substantia nigra, caudate nucleus and putamen but also in the olfactory tubercle.


CONCLUSIONS
These results demonstrate that MPTP causes both PD-like symptoms and olfactory disturbance in the common marmoset. The olfactory disturbance observed in these animals may be due to the lack of dopamine in the olfactory tubercle.
Department of Otorhinolaryngology, Kanazawa University Graduate School of Medicine, Kanazawa, Japan. miwataka@orl.m.kanazawa-u.ac.jp
Takaki
T
Miwa
Akihito
A
Watanabe
Yasuhide
Y
Mitsumoto
Mitsuru
M
Furukawa
Nanae
N
Fukushima
Tetsuji
T
Moriizumi
D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine / Q000009:adverse effects*; D000818:Animals; D002144:Callithrix; D003342:Corpus Striatum / Q000737:chemistry; D004195:Disease Models, Animal; D004298:Dopamine / Q000032:analysis; D015259:Dopamine Agents / Q000009:adverse effects*; D005260:Female; D007150:Immunohistochemistry; D008636:Mesencephalon / Q000737:chemistry; D000857:Olfaction Disorders / Q000139:chemically induced* / Q000503:physiopathology; D010302:Parkinson Disease, Secondary / Q000139:chemically induced* / Q000503:physiopathology
D015259:Dopamine Agents; D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; D004298:Dopamine