Calcium-dependent release of NO from intracellular S-nitrosothiols
Calcium-dependent release of NO from intracellular S-nitrosothiols
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DOI：
10.1038/sj.emboj.7601207
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发表时间：
2006-07-12
期刊：
影响因子：
11.4
通讯作者：
Tepikin, Alexei V.
中科院分区：
文献类型：
--
作者：
Chvanov, Michael;Gerasimenko, Oleg V.;Tepikin, Alexei V.
本文描述了一种新的细胞机制，快速钙依赖性一氧化氮（NO）的释放。这种释放是由于从S-亚硝基硫醇释放NO而发生的。本文分析了急性分离胰腺腺泡细胞中NO浓度的变化。超最大乙酰胆碱（ACh）刺激诱导的Ca 2+依赖性的增加，在大多数细胞中的荧光装载NO探针DAF-FM通过贴片移液管。ACh诱导的NO信号对钙调蛋白和蛋白激酶C抑制剂不敏感，但可被钙蛋白酶拮抗剂抑制。10 μ M乙酰胆碱诱导的NO信号的初始部分表现出对NO合酶（NOS）抑制的敏感性很小;然而，NO供体（增加细胞S-亚硝基硫醇含量）的细胞预处理大大增强了NO反应的初始成分。胰腺腺泡细胞能够产生快速的钙依赖性NO反应时，刺激生理或超大剂量的促分泌素。重要的是，这种NO的来源是已经可用的S-亚硝基硫醇储存，而不是NOS的从头合成。背根神经节神经元也有类似的NO释放机制。
The paper describes a novel cellular mechanism for rapid calcium-dependent nitric oxide (NO) release. This release occurs due to NO liberation from S-nitrosothiols. We have analysed the changes of NO concentration in acutely isolated pancreatic acinar cells. Supramaximal acetylcholine (ACh) stimulation induced a Ca2+-dependent increase in the fluorescence in the majority of cells loaded with the NO probe DAF-FM via a patch pipette. The ACh-induced NO signals were insensitive to inhibitors of calmodulin and protein kinase C but were inhibited by calpain antagonists. The initial part of the NO signals induced by 10 mu M ACh showed little sensitivity to inhibition of NO synthase (NOS); however, cell pretreatment with NO donors (increasing cellular S-nitrosothiol contents) substantially enhanced the initial component of NO responses. Pancreatic acinar cells were able to generate fast calcium-dependent NO responses when stimulated with physiological or supramaximal doses of secretagogues. Importantly, the source of this NO is the already available S-nitrosothiol store rather than de novo synthesis by NOS. A similar mechanism of NO release was found in dorsal root ganglia neurons.