The age-associated changes of dopamine-acetylcholine interaction in the striatum.
The age-associated decline of dopamine D2 receptor (D2R) densities is one of the notable features of aging in mammalian brains. The concept of a functional dopamine (DA)-acetylcholine (ACh) interaction in the striatum has been strongly supported. However, the effects of this decline of D2R on the striatal DA-ACh interaction still remain to be elucidated. In the current study we examined the effects of different concentrations of a D2R agonist, quinpirole, on the striatal ACh release in three groups of rats at different ages (6-, 15-, 25-months-old) by in vivo microdialysis. The ACh release in the striatum was significantly decreased by quinpirole infusion in all three age groups. The old rats showed a significantly smaller decrease of the ACh release by quinpirole than that of the middle-aged rats at the dose of 0.1 microM and that of the young rats at the dose of 1 microM. The current study suggested that the striatal DA-ACh interaction was affected by the aging process.
Kurotani
Shinobu
S
Department of Geriatrics, Nagoya University Graduate School of Medicine, 65 Tsuruma-Cho, Showa-Ku, Nagoya, Aichi 466-8550, Japan.
Umegaki
Hiroyuki
H
Ishiwata
Kiichi
K
Suzuki
Yusuke
Y
Iguchi
Akihisa
A
D000109:Acetylcholine / Q000378:metabolism*; D000375:Aging / Q000378:metabolism*; D000818:Animals; D003342:Corpus Striatum / Q000187:drug effects / Q000378:metabolism*; D004298:Dopamine / Q000378:metabolism*; D018491:Dopamine Agonists / Q000494:pharmacology; D008297:Male; D017551:Microdialysis / Q000379:methods; D019257:Quinpirole / Q000494:pharmacology; D051381:Rats; D011916:Rats, Inbred F344
D018491:Dopamine Agonists; D019257:Quinpirole; D000109:Acetylcholine; D004298:Dopamine