D2アゴニスト効果のポストシナプス発現に必要なD1ドーパミン受容体の活性化
Science (New York, N.Y.)
|May 8, 1987
まとめ
D1およびD2ドーパミン受容体の同時刺激は,ベースガンジリアニューロンと行動に対するドーパミン媒介の効果のために必要です. この発見は,D2受容体が単独でこれらの反応を媒介するという見解に異議を唱える.
科学分野:
- 神経科学は神経科学である.
- 薬理学 薬理学とは
- 行動科学は,行動科学である.
背景:
- ドーパミン受容体,特にD1およびD2サブタイプは,基礎性腺機能と運動行動を調節する上で重要な役割を果たします.
- 以前の研究では,D2ドーパミン受容体がドーパミンアゴニストによって誘発される行動および神経生理学的変化を独立して媒介することが示唆されていた.
研究 の 目的:
- ベースガンリアのニューロン活動と運動行動におけるD1およびD2ドーパミン受容体の相乗効果的役割を調査する.
- D2受容体媒介作用が,内生ドーパミンによる同時進行中のD1受容体刺激に依存しているかどうかを判断する.
主な方法:
- ネズミの基礎ガンジリアニューロンの電気生理学的記録.
- 自発的な運動活動とステレオタイプ行動の評価.
- D1およびD2ドーパミン受容体アゴニストおよびアンタゴニストを用いた薬理学的操作.
- アルファメチルロチロシンを使用した内生ドーパミンの枯渇.
主要な成果:
- D2選択性アゴニストの神経生理学的および行動的効果は,内生ドーパミンが枯渇したネズミで著しく弱まった.
- 非選択的ドーパミンアゴニストまたはD1およびD2アゴニストの組み合わせは,内生ドーパミン濃度に関係なく,強力な効果を生成しました.
- これらの発見は,D2受容体アゴニストの有効性は,D1受容体で作用する内生ドーパミンに依存することを示しています.
結論:
- この結果は,D2ドーパミン受容体が単独でドーパミン誘発によるベースガンリア出力および行動の変化を媒介するという考え方に異議を唱えている.
- これらの効果には,ドーパミン受容体D1とD2の両方の同時刺激が必要である.
- D1およびD2ドーパミン受容体間の相乗効果相互作用は,基礎性腺機能と運動制御の調節に不可欠です.
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