一个PACAP激活的分泌网络需要协调Ca2+流入和Ca2+调动
bioRxiv : the preprint server for biology
|January 23, 2024
概括
垂体腺酸激活聚 (PACAP) 触发了从上腺胺细胞中持续释放的压力激素. 这种持续的分泌依赖于一个信号网络,涉及的调动和流入,由脂酶Cepsilon (PLCε) 调节.
科学领域:
- 神经内分泌学神经内分泌学
- 细胞信号传输 细胞信号传输
背景情况:
- 克罗马芬细胞调解应激激素的分泌,以应对交感神经活动.
- 乙胆和 pituitary adenylate activating polypeptide (PACAP) 是关键的神经递质,但PACAP持续分泌的机制尚不清楚.
研究的目的:
- 为了阐明人们对PACAP在克罗马芬细胞中持续的分泌反应背后的不太了解的机制.
- 为了确定由PACAP诱导的长期细胞内 (Ca2+) 升高的信号通路.
主要方法:
- 研究了Ca2+通过L型通道和内部Ca2+储存在PACAP介导反应中的作用.
- 研究了内醇三酸盐受体 (IP3Rs) 在Ca2+调动中的内质网膜 (ER) 的参与.
- 评估了这些途径对脂酶Cepsilon (PLCε) 活性的依赖性.
主要成果:
- PACAP诱导持续的细胞溶液Ca2+增加,这取决于Ca2+涌入和内部Ca2+储存释放.
- 通过IP3Rs从ER中释放PACAP引起的Ca2+功能性地与Ca2+流入配对,支持Ca2+诱导的Ca2+释放.
- 两种Ca2+流入和调动途径都严重依赖于脂酶Cepsilon (PLCε) 活性.
结论:
- PACAP通过一个信号网络调节持续的氨酸细胞分泌,促进持续的细胞内Ca2+升高.
- 这个网络整合了Ca2+的动员和流入通道,突出了PLCε的中心作用.
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