カテコロアミンの吸収は,副腎中枢の粒子分泌によって行われます
Science (New York, N.Y.)
|January 12, 1962
まとめ
牛の副腎髄クロマフィン粒子は,カタチョラミンを積極的に輸送する. マグネシウムとATPは,この吸収を著しく強化し,レザーピンとEDTAによって抑制されます.
科学分野:
- バイオケミストリー バイオケミストリー
- 細胞生物学 細胞生物学
- 神経科学は神経科学である.
背景:
- クロマフィン粒子は,副腎髄におけるカテキオラミンの鍵となる貯蔵ベジクルである.
- カテキオラミン輸送の理解は,神経内分泌研究にとって極めて重要です.
研究 の 目的:
- 孤立したクロマフィン粒子がカテキオラミンを吸収するメカニズムを調査する.
- これらの膀におけるカテキオラミン輸送に影響を与える要因を特定する.
主な方法:
- 牛の副腎髄からクロマフィン粒子を分離する.
- 異なる温度 (0°C vs. 37°C) でC(14) ラベル付きカテキオラミンの摂取量を測定する.
- Mg ((++),アデノシン・トリフォスファート (ATP),レザーピン,エチレン・ダイアミネ・テトラエセチック酸 (EDTA) の摂取に対する影響の評価.
主要な成果:
- カテコロアミンの吸収は,0°Cと比較して37°Cで有意に増加し,活発なプロセスを示した.
- 吸収はMg (((++)) とATPによって3〜5倍に刺激されました.
- レザーピン (1 x 10(-5) M) は90%の吸収を阻害しました.
- EDTAはMgとATP刺激による吸収を完全に阻害しましたが,過剰なMgとMgとでこの阻害は逆転することができました.
結論:
- クロマフィン粒子は,カテキオラミンの活性輸送システムを備えています.
- この輸送システムは,Mg ((++) とATPに依存しています.
- この発見は,Mg ((++) に依存するATPアゼが,クロマフィン粒子のカテキオラミンの吸収に関与していることを示唆している.
キーワード:
副腎髄/代謝について
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