莱普通过激活对ATP敏感的通道来抑制下丘脑神经元
D Spanswick1, M A Smith, V E Groppi
1Department of Biomedical Sciences, University of Aberdeen, Institute of Medical Sciences, Foresterhill, UK.
Nature
|December 11, 1997
概括
瘦鼠中,瘦素是体重调节的关键激素,它激活了瘦鼠下丘脑中的通道. 这种对控制食欲至关重要的机制在肥胖老鼠中受损,这表明与糖尿病有关.
科学领域:
- 神经内分泌学神经内分泌学
- 分子生物学分子生物学
- 代谢调节 代谢调节 代谢调节
背景情况:
- 脂肪组织分泌的瘦素通过中枢神经系统,特别是下丘脑,调节食物摄入量和体重.
- 丁或其下丘脑受体 (Ob-R[L]) 的突变导致肥胖和非胰岛素依赖性糖尿病.
研究的目的:
- 为了研究瘦素对下丘脑神经元的直接作用.
- 为了确定特定的离子通道和分子机制涉及莱普在下丘脑的作用.
主要方法:
- 精瘦和肥胖的Zucker大鼠的下丘脑神经元上的电生理学记录 (全细胞和单通道).
- 丁和托尔布塔米德的应用,以评估神经元反应.
- 对流和对ATP敏感的通道 (KATP) 的分析.
主要成果:
- 瘦老鼠的低质体中接受葡萄糖的神经元中,莱普诱导过极化,但不是肥胖的Zucker (fa/fa) 鼠.
- 这种超极化归因于电流的激活.
- 单通道记录证实了素直接激活对ATP敏感的 (KATP) 通道.
- 叶丁诱导的效应被硫基尿素药物托尔布塔米德逆转.
结论:
- 莱普激活了大脑下丘脑神经元中的KATP通道,这表明该通道是莱普信号传递的关键分子标.
- 在肥胖大鼠中,丁诱导的KATP通道激活受损可能会导致肥胖和糖尿病的病理生理学.
- 这项研究阐明了勒普丁在代谢控制中的作用背后的关键细胞机制.
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