Human diving is known to induce endothelial dysfunction. The aim of this study was to decipher the mechanism of ROS production during diving through the measure of mitochondrial calcium concentration, peroxynitrite, NO°, and superoxide towards better understanding of dive-induced endothelial dysfunction. Air diving simulation using bovine arterial endothelial cells (compression rate 101 kPa/min to 808 kPa, time at depth 45 min) was performed in a system allowing real-time fluorescent measurement. During compression, the cells showed increased mitochondrial superoxide, peroxynitrite, and mitochondrial calcium, and decreased NO° concentration. MnTBAP (peroxynitrite scavenger) suppressed superoxide, recovered NO° production and promoted stronger calcium influx. Superoxide and peroxynitrite were inhibited by L-NIO (eNOS inhibitor), but were further increased by spermine-NONOate (NO° donor). L-NIO induced stronger calcium influx than spermine-NONOate or simple diving. The superoxide and peroxynitrite were also inhibited by ruthenium red (blocker of mitochondrial Ca²⁺ uniporter), but were increased by CGP (an inhibitor of mitochondrial Na⁺-Ca²⁺ exchange). Reactive oxygen and nitrogen species changes are associated, together with calcium mitochondrial storage, with endothelial cell dysfunction during simulated diving. Peroxynitrite is involved in NO° loss, possibly through the attenuation of eNOS and by increasing superoxide which combines with NO° and forms more peroxynitrite. In the field of diving physiology, this study is the first to unveil a part of the cellular mechanisms of ROS production during diving and confirms that diving-induced loss of NO° is linked to superoxide and peroxynitrite.

中文翻译：

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模拟空气潜水在内皮细胞中诱导超氧化物，一氧化氮，过氧亚硝酸盐和Ca 2+改变

众所周知，人类跳水会诱发内皮功能障碍。这项研究的目的是通过测量线粒体钙浓度，过氧亚硝酸盐，NO°和超氧化物来解释潜水过程中ROS的产生机制，以更好地了解潜水引起的内皮功能障碍。在允许实时荧光测量的系统中，使用牛动脉内皮细胞进行空气潜水模拟（压缩率101 kPa / min至808 kPa，深度45分钟）。在压缩过程中，细胞显示线粒体超氧化物，过氧亚硝酸盐和线粒体钙增加，而NO°浓度降低。MnTBAP（过亚硝酸盐清除剂）抑制超氧化物，恢复NO°的产生并促进更强的钙流入。L-NIO（eNOS抑制剂）可抑制超氧化物和过氧亚硝酸盐，但精胺-NONOate（NO°供体）进一步增加。L-NIO比精胺-NONOate或简单潜水引起的钙流入更强。钌红（线粒体钙的阻滞剂）也能抑制过氧化物和过亚硝酸盐。²⁺单向转运蛋白，但被CGP（线粒体Na ⁺ -Ca ²⁺交换抑制剂）增加。在模拟潜水过程中，活性氧和氮的种类变化以及线粒体钙的储存与内皮细胞功能障碍有关。过氧亚硝酸盐可能参与了NO°的损失，可能是通过eNOS的衰减以及与NO°结合并形成更多过氧亚硝酸盐的超氧化物的增加。在潜水生理学领域，这项研究是第一个揭示潜水过程中ROS产生的细胞机制的一部分的研究，并证实了潜水引起的NO°的损失与超氧化物和过氧亚硝酸盐有关。