概括
对于上腺细胞来说是必不可少的,以产生皮质和循环腺单酸盐,以应对 adrenocorticotropic 激素. 增加细胞外增强了这些反应,这表明腺环酶具有独特的细胞内环境.
科学领域:
- 内分泌学 在内分泌学.
- 细胞生物学 细胞生物学
- 生物化学 生物化学
背景情况:
- 上腺皮质激素 (ACTH) 在上腺细胞中刺激皮质的产生.
- 循环腺单酸盐 (cAMP) 是这个信号通路中的关键的第二信使.
- 细胞外在ACTH刺激的类固醇生成和cAMP积累中的作用尚未完全理解.
研究的目的:
- 研究细胞外的度对ACTH诱导的皮质生产和单独的上腺细胞中的cAMP积累的影响.
- 为了比较完整的上腺细胞与亚细胞膜碎片中的腺环酶的敏感性.
主要方法:
- 隔离的老鼠上腺细胞被化在具有不同度 (0-7.65 mM) 的介质中.
- 使用已建立的测定方法测量皮质激素的产量.
- 量化了细胞内cAMP水平.
- 还使用上腺组织的亚细胞膜碎片进行了实验.
主要成果:
- 在没有细胞外的情况下,皮质的产生和cAMP的积累显著减少.
- 从0到7.65mM增加细胞外的度,相应地增加了皮质激素的产生和cAMP的积累.
- 相比之下,高 (> 1.0 mM) 抑制了亚细胞膜碎片中cAMP的积累,表明完整的细胞和隔离的膜之间的差异.
结论:
- 细胞外在介导ACTH刺激的皮质生产和cAMP信号传递在完整的上腺细胞中起着至关重要的作用.
- 在完好无损的上腺细胞中的腺环酶似乎在低的环境中被细分,对细胞外的波动不敏感.
- 这些发现表明一种模型,即细胞外的增加增强了信号传导到腺环酶区的信号传导.
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