海馬ドーパミンD2受容体と記憶・前頭葉機能との関わり
Abstract
認知機能や記憶機能は線条体外の前頭前野や海馬といった皮質領域と深く関わっている。サルやヒトを対象とした研究で前頭前野のドーパミンD1受容体が認知機能に重要な役割を果たしていることが知られているが、ドーパミンD2受容体はD1受容体に比べると線条体外では分布密度が小さく、認知機能との関連は不明な点が多い。D2受容体に高い親和性を有するリガンドである[11C]FLB 457を用いることによって線条体外のD2受容体と認知機能との関連をPositron Emission Tomography (PET)にて検討した。対象は20才代、30才代の健常男性25人でPET施行後、各種神経心理学的検査を行った。海馬におけるD2受容体結合能と記憶機能との間に正の相関を認めた。さらに海馬D2受容体結合能と遂行機能、語流暢性といった前頭葉機能との間にも正の相関を認め、海馬D2受容体が記憶機能のみならず認知機能に重要な役割を担っていることが示唆された。第46回日本核医学会学術総Similar works
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National Institute of Radiological Science: NIRS-Repository / 放射線医学総合研究所 学術機関リポジトリ
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oai:repo.qst.go.jp:000...Last time updated on 30/10/2019
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This paper was published in National Institute of Radiological Science: NIRS-Repository / 放射線医学総合研究所 学術機関リポジトリ.
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