GABAは, pituitary pars intermediaの細胞に直接作用し,ホルモンの産出量を変化させます
Nature
|February 24, 1983
まとめ
ガンマ・アミノバター酸 (GABA) が下垂体内を刺激すると,メラノサイト刺激ホルモン (MSH) の分泌に影響を与えます. GABA受容体は,メラノトロフの電気的性質とホルモン放出の両方を調節する.
科学分野:
- 神経内分泌学の神経内分泌学
- 下垂体腺生理学 下垂体腺生理学
- 神経伝達物質の機能 神経伝達物質の機能
背景:
- GABAを含む繊維によって下垂体パースインターメディアの中枢神経系内化が最近ラットで確認されています.
- ガンマ-アミノバター酸 (GABA) は,ビキュキュリンで遮断可能な受容体を通してメラノトロフに作用し,塩化物の伝導性と膜ポテンシャルに影響を及ぼすことが知られている.
研究 の 目的:
- pituitary pars intermedia.におけるGABAergic 内置の機能的役割を調査する.
- メラノトロフホルモンの分泌と電気的特性に対するGABAの影響を調べる.
主な方法:
- 孤立したラットメラノトロフの電気生理学的記録.
- GABA受容体の薬理学的特徴.
- メラノサイト刺激ホルモン (MSH) の分泌の自発的および誘発的測定.
主要な成果:
- GABAは最初は刺激し,その後は自発的なMSHの分泌を抑制する.
- GABAは,カリウムの誘発によるMSHの分泌を抑制する.
- 薬理学的証拠は,共有された受容体が電気生理学的および分泌反応を媒介することを示しています.
結論:
- GABAergic内置は,下垂体メラノトロフからホルモンの放出を直接調節する.
- GABAの電気特性への影響は,MSH分泌の調節と関連しています.
- これは,ホルモン放出の神経内分泌制御のためのメカニズムを示唆しています.
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